diff --git a/vlib/builtin/cfns.c.v b/vlib/builtin/cfns.c.v
index fd069629f3..d5a06f543b 100644
--- a/vlib/builtin/cfns.c.v
+++ b/vlib/builtin/cfns.c.v
@@ -213,7 +213,7 @@ fn C.GetModuleFileNameW(hModule voidptr, lpFilename &u16, nSize u32) u32
 fn C.CreatePipe(hReadPipe &voidptr, hWritePipe &voidptr, lpPipeAttributes voidptr, nSize u32) bool
 
 
-fn C.SetHandleInformation(hObject voidptr, dwMask u32, dwFlags u32) bool
+fn C.SetHandleInformation(hObject voidptr, dwMask u32, dw_flags u32) bool
 
 
 fn C.ExpandEnvironmentStringsW(lpSrc &u16, lpDst &u16, nSize u32) u32
@@ -228,7 +228,7 @@ fn C.ReadFile(hFile voidptr, lpBuffer voidptr, nNumberOfBytesToRead u32, lpNumbe
 fn C.GetFileAttributesW(lpFileName byteptr) u32
 
 
-fn C.RegQueryValueExW(hKey voidptr, lpValueName &u16, lpReserved &u32, lpType &u32, lpData byteptr, lpcbData &u32) int
+fn C.RegQueryValueExW(hKey voidptr, lpValueName &u16, lp_reserved &u32, lpType &u32, lpData byteptr, lpcbData &u32) int
 
 
 fn C.RegOpenKeyExW(hKey voidptr, lpSubKey &u16, ulOptions u32, samDesired u32, phkResult voidptr) int
diff --git a/vlib/builtin/int_test.v b/vlib/builtin/int_test.v
index b62682d093..2381d43b9d 100644
--- a/vlib/builtin/int_test.v
+++ b/vlib/builtin/int_test.v
@@ -31,7 +31,6 @@ fn test_float_equal_operator() {
 	assert a.gebit(1)
 	assert -1 == 1 * -1
 	assert -1.0 == 1.0 * -1.0
-
 	a = f64(1)
 	a += 0.000001
 	a -= 0.000001
@@ -47,7 +46,6 @@ fn test_float_equal_operator() {
 	assert a.gtbit(f32(1))
 	assert a >= 1
 	assert a.gebit(1)
-
 	f := 1.2
 	ab := int(f)
 	assert ab == 1
@@ -62,7 +60,6 @@ fn test_str_methods() {
 	assert int(-1).str() == '-1'
 	assert i64(1).str() == '1'
 	assert i64(-1).str() == '-1'
-
 	// assert byte(1).str() == '1'
 	// assert byte(-1).str() == '255'
 	assert u16(1).str() == '1'
@@ -131,17 +128,11 @@ fn test_cmp() {
 	assert 1 ⩾ 0
 }
 */
-
-type myint int
-type mystring string
+type MyInt int
 
 fn test_int_alias() {
-	/*
-	i := myint(2)
-	s := mystring('hi')
-	ss := s + '!'
+	i := MyInt(2)
 	assert i + 10 == 12
-	*/
 }
 
 fn test_hex() {
@@ -194,49 +185,43 @@ fn test_int_decl() {
 
 fn test_int_to_hex() {
 	// array hex
-	st := [byte(`V`),`L`,`A`,`N`,`G`]
-	assert st.hex() == "564c414e47"
+	st := [byte(`V`), `L`, `A`, `N`, `G`]
+	assert st.hex() == '564c414e47'
 	assert st.hex().len == 10
-
 	st1 := [byte(0x41)].repeat(100)
-	assert st1.hex() == "41".repeat(100)
-
-	//--- int to hex tests
+	assert st1.hex() == '41'.repeat(100)
+	// --- int to hex tests
 	c0 := 12
-
 	// 8Bit
-	assert byte(0).hex()   == "0"
-	assert byte(c0).hex()  == "c"
-	assert i8(c0).hex()    == "c"
-	assert byte(127).hex() == "7f"
-	assert i8(127).hex()   == "7f"
-	assert byte(255).hex() == "ff"
-	assert byte(-1).hex()  == "ff"
-
+	assert byte(0).hex() == '0'
+	assert byte(c0).hex() == 'c'
+	assert i8(c0).hex() == 'c'
+	assert byte(127).hex() == '7f'
+	assert i8(127).hex() == '7f'
+	assert byte(255).hex() == 'ff'
+	assert byte(-1).hex() == 'ff'
 	// 16bit
-	assert u16(0).hex()      == "0"
-	assert i16(c0).hex()     == "c"
-	assert u16(c0).hex()     == "c"
-	assert i16(32767).hex()  == "7fff"
-	assert u16(32767).hex()  == "7fff"
-	assert i16(-1).hex()     == "ffff"
-	assert u16(65535).hex()  == "ffff"
-
+	assert u16(0).hex() == '0'
+	assert i16(c0).hex() == 'c'
+	assert u16(c0).hex() == 'c'
+	assert i16(32767).hex() == '7fff'
+	assert u16(32767).hex() == '7fff'
+	assert i16(-1).hex() == 'ffff'
+	assert u16(65535).hex() == 'ffff'
 	// 32bit
-	assert u32(0).hex()           == "0"
-	assert c0.hex()               == "c"
-	assert u32(c0).hex()          == "c"
-	assert 2147483647.hex()       == "7fffffff"
-	assert u32(2147483647).hex()  == "7fffffff"
-	assert (-1).hex()             == "ffffffff"
-	assert u32(4294967295).hex()  == "ffffffff"
-
+	assert u32(0).hex() == '0'
+	assert c0.hex() == 'c'
+	assert u32(c0).hex() == 'c'
+	assert 2147483647.hex() == '7fffffff'
+	assert u32(2147483647).hex() == '7fffffff'
+	assert (-1).hex() == 'ffffffff'
+	assert u32(4294967295).hex() == 'ffffffff'
 	// 64 bit
-	assert u64(0).hex()                      == "0"
-	assert i64(c0).hex()                     == "c"
-	assert u64(c0).hex()                     == "c"
-	assert i64(9223372036854775807).hex()    == "7fffffffffffffff"
-	assert u64(9223372036854775807).hex()    == "7fffffffffffffff"
-	assert i64(-1).hex()                     == "ffffffffffffffff"
-	assert u64(18446744073709551615).hex()   == "ffffffffffffffff"
+	assert u64(0).hex() == '0'
+	assert i64(c0).hex() == 'c'
+	assert u64(c0).hex() == 'c'
+	assert i64(9223372036854775807).hex() == '7fffffffffffffff'
+	assert u64(9223372036854775807).hex() == '7fffffffffffffff'
+	assert i64(-1).hex() == 'ffffffffffffffff'
+	assert u64(18446744073709551615).hex() == 'ffffffffffffffff'
 }
diff --git a/vlib/builtin/string_test.v b/vlib/builtin/string_test.v
index 0aa21eeb01..ec4eca568d 100644
--- a/vlib/builtin/string_test.v
+++ b/vlib/builtin/string_test.v
@@ -766,3 +766,12 @@ fn test_string_literal_with_backslash(){
 		  Three'
 	assert b == 'OneTwoThree'
 }
+
+/*
+type MyString string
+
+fn test_string_alias() {
+	s := MyString('hi')
+	ss := s + '!'
+}
+*/
diff --git a/vlib/clipboard/clipboard_windows.c.v b/vlib/clipboard/clipboard_windows.c.v
index 3f413f92f6..072f5e649d 100644
--- a/vlib/clipboard/clipboard_windows.c.v
+++ b/vlib/clipboard/clipboard_windows.c.v
@@ -3,49 +3,62 @@ module clipboard
 import time
 
 struct WndClassEx {
-	cbSize u32
-    style u32
-    lpfnWndProc voidptr
-    cbClsExtra int
-    cbWndExtra int
-  	hInstance C.HINSTANCE
-    hIcon C.HICON
-    hCursor C.HCURSOR
-    hbrBackground C.HBRUSH
-    lpszMenuName &u16 // LPCWSTR
-    lpszClassName &u16
-    hIconSm &u16
+	cb_size         u32
+	style           u32
+	lpfn_wnd_proc   voidptr
+	cb_cls_extra    int
+	cb_wnd_extra    int
+	h_instance      C.HINSTANCE
+	h_icon          C.HICON
+	h_cursor        C.HCURSOR
+	hbr_background  C.HBRUSH
+	lpsz_menu_name  &u16 // LPCWSTR
+    lpsz_class_name &u16
+	h_icon_sm       &u16
 }
 
 fn C.RegisterClassEx(class WndClassEx) int
+
 fn C.GetClipboardOwner() &C.HWND
-fn C.CreateWindowEx(dwExStyle i64, lpClassName &u16, lpWindowName &u16, dwStyle i64, x int, y int, nWidth int, nHeight int, hWndParent i64, hMenu voidptr, hInstance voidptr, lpParam voidptr) &C.HWND
-//fn C.MultiByteToWideChar(CodePage u32, dwFlags u16, lpMultiByteStr byteptr, cbMultiByte int, lpWideCharStr u16, cchWideChar int) int
+
+fn C.CreateWindowEx(dwExStyle i64, lpClassName, lpWindowName &u16, dwStyle i64, x, y, nWidth, nHeight int, hWndParent i64, hMenu, h_instance, lpParam voidptr) &C.HWND
+
+// fn C.MultiByteToWideChar(CodePage u32, dw_flags u16, lpMultiByteStr byteptr, cbMultiByte int, lpWideCharStr u16, cchWideChar int) int
 fn C.EmptyClipboard()
+
 fn C.CloseClipboard()
+
 fn C.GlobalAlloc(uFlag u32, size i64) C.HGLOBAL
+
 fn C.GlobalFree(buf C.HGLOBAL)
+
 fn C.GlobalLock(buf C.HGLOBAL)
+
 fn C.GlobalUnlock(buf C.HGLOBAL)
+
 fn C.SetClipboardData(uFormat u32, data voidptr) C.HANDLE
+
 fn C.GetClipboardData(uFormat u32) C.HANDLE
+
 fn C.DefWindowProc(hwnd C.HWND, msg u32, wParam C.WPARAM, lParam C.LPARAM) C.LRESULT
+
 fn C.SetLastError(error i64)
+
 fn C.OpenClipboard(hwnd C.HWND) int
+
 fn C.DestroyWindow(hwnd C.HWND)
 
 struct Clipboard {
     max_retries int
     retry_delay int
     mut:
-    hwnd C.HWND
-    foo int // TODO remove
+	hwnd        C.HWND
+	foo         int // TODO remove
 }
 
 fn (cb &Clipboard) get_clipboard_lock() bool {
 	mut retries := cb.max_retries
 	mut last_error := u32(0)
-
 	for {
 		retries--
 		if retries < 0 {
@@ -57,7 +70,6 @@ fn (cb &Clipboard) get_clipboard_lock() bool {
         } else if last_error != u32(C.ERROR_ACCESS_DENIED) {
             return false
         }
-
 		time.sleep(cb.retry_delay)
 	}
     C.SetLastError(last_error)
@@ -65,24 +77,25 @@ fn (cb &Clipboard) get_clipboard_lock() bool {
 }
 
 fn new_clipboard() &Clipboard {
-    mut cb := &Clipboard {
+	mut cb := &Clipboard{
         max_retries: 5
         retry_delay: 5
     }
-	class_name := "clipboard"
-    wndclass := WndClassEx {
-        cbSize: sizeof(WndClassEx)
-        lpfnWndProc: voidptr(&C.DefWindowProc)
-        lpszClassName: class_name.to_wide()
-		lpszMenuName: 0
-		hIconSm: 0
+	class_name := 'clipboard'
+	wndclass := WndClassEx{
+        cb_size: sizeof(WndClassEx)
+        lpfn_wnd_proc: voidptr(&C.DefWindowProc)
+        lpsz_class_name: class_name.to_wide()
+		lpsz_menu_name: 0
+		h_icon_sm: 0
     }
     if C.RegisterClassEx(&wndclass) == 0 && C.GetLastError() != u32(C.ERROR_CLASS_ALREADY_EXISTS) {
-        println("Failed registering class.")
+		println('Failed registering class.')
     }
-    hwnd := C.CreateWindowEx(0, wndclass.lpszClassName, wndclass.lpszClassName, 0, 0, 0, 0, 0, C.HWND_MESSAGE, C.NULL, C.NULL, C.NULL)
+	hwnd := C.CreateWindowEx(0, wndclass.lpsz_class_name, wndclass.lpsz_class_name, 0, 0, 0,
+		0, 0, C.HWND_MESSAGE, C.NULL, C.NULL, C.NULL)
     if hwnd == C.NULL {
-        println("Error creating window!")
+		println('Error creating window!')
     }
     cb.hwnd = hwnd
     return cb
@@ -96,21 +109,24 @@ fn (cb &Clipboard) has_ownership() bool {
     return C.GetClipboardOwner() == cb.hwnd
 }
 
-fn (cb mut Clipboard) clear() {
-    if !cb.get_clipboard_lock() {return}
+fn (mut cb Clipboard) clear() {
+	if !cb.get_clipboard_lock() {
+		return
+	}
     C.EmptyClipboard()
     C.CloseClipboard()
 	cb.foo = 0
 }
 
-fn (cb mut Clipboard) free(){
+fn (mut cb Clipboard) free() {
     C.DestroyWindow(cb.hwnd)
 	cb.foo = 0
 }
 
 // the string.to_wide doesn't work with SetClipboardData, don't know why
 fn to_wide(text string) &C.HGLOBAL {
-    len_required := C.MultiByteToWideChar(C.CP_UTF8, C.MB_ERR_INVALID_CHARS, text.str, text.len + 1, C.NULL, 0)
+	len_required := C.MultiByteToWideChar(C.CP_UTF8, C.MB_ERR_INVALID_CHARS, text.str, text.len +
+		1, C.NULL, 0)
     buf := C.GlobalAlloc(C.GMEM_MOVEABLE, sizeof(u16) * len_required)
     if buf != C.HGLOBAL(C.NULL) {
         mut locked := &u16(C.GlobalLock(buf))
@@ -121,7 +137,7 @@ fn to_wide(text string) &C.HGLOBAL {
     return buf
 }
 
-fn (cb mut Clipboard) set_text(text string) bool {
+fn (mut cb Clipboard) set_text(text string) bool {
 	cb.foo = 0
     buf := to_wide(text)
     if !cb.get_clipboard_lock() {
@@ -131,7 +147,7 @@ fn (cb mut Clipboard) set_text(text string) bool {
         // EmptyClipboard must be called to properly update clipboard ownership
         C.EmptyClipboard()
         if C.SetClipboardData(C.CF_UNICODETEXT, buf) == C.HANDLE(C.NULL) {
-            println("SetClipboardData: Failed.")
+			println('SetClipboardData: Failed.')
             C.CloseClipboard()
             C.GlobalFree(buf)
             return false
@@ -142,15 +158,15 @@ fn (cb mut Clipboard) set_text(text string) bool {
     return true
 }
 
-fn (cb mut Clipboard) get_text() string {
+fn (mut cb Clipboard) get_text() string {
 	cb.foo = 0
     if !cb.get_clipboard_lock() {
-        return ""
+		return ''
     }
     h_data := C.GetClipboardData(C.CF_UNICODETEXT)
     if h_data == C.HANDLE(C.NULL) {
         C.CloseClipboard()
-        return ""
+		return ''
     }
     str := string_from_wide(&u16(C.GlobalLock(h_data)))
     C.GlobalUnlock(h_data)
diff --git a/vlib/encoding/utf8/utf8_util.v b/vlib/encoding/utf8/utf8_util.v
index f21fa6b36b..14d1dab3dc 100644
--- a/vlib/encoding/utf8/utf8_util.v
+++ b/vlib/encoding/utf8/utf8_util.v
@@ -164,27 +164,27 @@ fn utf8util_char_len(b byte) int {
 //
 // up_low make the dirt job
 fn up_low(s string, upper_flag bool) string {
-	mut _index := 0
+	mut index := 0
 	mut str_res := malloc(s.len + 1)
 
 	for {
-		ch_len := utf8util_char_len(s.str[_index])
+		ch_len := utf8util_char_len(s.str[index])
 
 		if ch_len == 1 {
 			if upper_flag==true {
-				str_res[_index] = C.toupper(s.str[_index])
+				str_res[index] = C.toupper(s.str[index])
 			}else{
-				str_res[_index] = C.tolower(s.str[_index])
+				str_res[index] = C.tolower(s.str[index])
 			}
 		}
 		else if ch_len > 1 && ch_len < 5{
 			mut lword := 0
 
 			for i:=0; i < ch_len ; i++ {
-				lword = (lword << 8 ) | int( s.str[_index + i] )
+				lword = (lword << 8 ) | int( s.str[index + i] )
 			}
 
-			//C.printf(" #%d (%x) ", _index, lword)
+			//C.printf(" #%d (%x) ", index, lword)
 
 			mut res := 0
 
@@ -215,7 +215,7 @@ fn up_low(s string, upper_flag bool) string {
 			// char not in table, no need of conversion
 			if ch_index == 0 {
 				for i in 0..ch_len {
-					str_res[_index + i] = s.str[_index + i]
+					str_res[index + i] = s.str[index + i]
 				}
 				//C.printf("\n")
 			}else{
@@ -227,13 +227,13 @@ fn up_low(s string, upper_flag bool) string {
 					ch1 := byte( (tab_char >> 0) & 0x3f ) | 0x80		/*10xx xxxx*/
 					//C.printf("[%02x%02x] \n",ch0,ch1)
 
-					str_res[ _index + 0 ] = ch0
-					str_res[ _index + 1 ] = ch1
+					str_res[ index + 0 ] = ch0
+					str_res[ index + 1 ] = ch1
 
 					//****************************************************************
 					//  BUG: doesn't compile, workaround use shitf to right of 0 bit
 					//****************************************************************
-					//str_res[_index + 1 ] = byte( tab_char & 0xbf )			/*1011 1111*/
+					//str_res[index + 1 ] = byte( tab_char & 0xbf )			/*1011 1111*/
 
 				}
 				else if ch_len == 3 {
@@ -242,16 +242,16 @@ fn up_low(s string, upper_flag bool) string {
 					ch2 := byte( (tab_char >> 0) & 0x3f ) | 0x80		/*10xx xxxx*/
 					//C.printf("[%02x%02x%02x] \n",ch0,ch1,ch2)
 
-					str_res[_index + 0 ] = ch0
-					str_res[_index + 1 ] = ch1
-					str_res[_index + 2 ] = ch2
+					str_res[index + 0 ] = ch0
+					str_res[index + 1 ] = ch1
+					str_res[index + 2 ] = ch2
 				}
 				// TODO: write if needed
 				else if ch_len == 4 {
 					// place holder!!
 					// at the present time simply copy the utf8 char
 					for i in 0..ch_len {
-						str_res[_index + i] = s.str[_index + i]
+						str_res[index + i] = s.str[index + i]
 					}
 				}
 			}
@@ -260,20 +260,20 @@ fn up_low(s string, upper_flag bool) string {
 		// other cases, just copy the string
 		else{
 			for i in 0..ch_len {
-				str_res[_index + i] = s.str[_index + i]
+				str_res[index + i] = s.str[index + i]
 			}
 		}
 
-		_index += ch_len
+		index += ch_len
 
 		// we are done, exit the loop
-		if _index >= s.len {
+		if index >= s.len {
 			break
 		}
 	}
 
 	// for c compatibility set the ending 0
-	str_res[_index]=0
+	str_res[index]=0
 
 	//C.printf("str_res: %s\n--------------\n",str_res)
 
@@ -1680,6 +1680,6 @@ unicode_punct=[
 0x1DA8A, // SIGNWRITING COLON	𝪊
 0x1DA8B, // SIGNWRITING PARENTHESIS	𝪋
 0x1E95E, // ADLAM INITIAL EXCLAMATION MARK	𞥞
-0x1E95F, // ADLAM INITIAL QUESTION MARK	
+0x1E95F, // ADLAM INITIAL QUESTION MARK
 ]
 )
diff --git a/vlib/freetype/freetype.v b/vlib/freetype/freetype.v
index 60e0e17b60..a114e79955 100644
--- a/vlib/freetype/freetype.v
+++ b/vlib/freetype/freetype.v
@@ -1,7 +1,6 @@
 // Copyright (c) 2019-2020 Alexander Medvednikov. All rights reserved.
 // Use of this source code is governed by an MIT license
 // that can be found in the LICENSE file.
-
 module freetype
 
 import os
@@ -9,19 +8,17 @@ import gx
 import gg
 import glm
 import gl
+
 /*
 TODO
 !!!!!!
 Use a font atlas
 !!!!!!
 */
-
 #flag windows -I @VROOT/thirdparty/freetype/include
 #flag windows -L @VROOT/thirdparty/freetype/win64
-
 #flag solaris -I/opt/local/include/freetype2
 #flag solaris -L/opt/local/lib
-
 #flag darwin -I/usr/local/include/freetype2
 // MacPorts
 #flag darwin -I/opt/local/include/freetype2
@@ -29,49 +26,39 @@ Use a font atlas
 #flag freebsd -I/usr/local/include/freetype2
 #flag freebsd -Wl -L/usr/local/lib
 #flag -lfreetype
-
-//#flag -I @VROOT/thirdparty/freetype
-
-//#flag @VROOT/thirdparty/freetype/libfreetype.a
+// #flag -I @VROOT/thirdparty/freetype
+// #flag @VROOT/thirdparty/freetype/libfreetype.a
 #flag darwin -lpng -lbz2 -lz
-
-
 #flag linux 	-I/usr/include/freetype2
 #flag linux -I.
-
-
 #include "ft2build.h"
 #include FT_FREETYPE_H
-
 fn C.FT_Init_FreeType() voidptr
+
 fn C.FT_New_Face() voidptr
+
 fn C.FT_Set_Pixel_Sizes()
 
-
-
 pub const (
 	default_font_size = 12
 )
 
 struct Character {
-	code i64
-
-	texture_id u32
-	size       gg.Vec2
-
+	code                  i64
+	texture_id            u32
+	size                  gg.Vec2
 	horizontal_bearing_px gg.Vec2
 	horizontal_advance_px u32
-
 	vertical_bearing_px   gg.Vec2
 	vertical_advance_px   u32
 }
 
 [typedef]
-struct C.FT_Library {}
+struct C.FT_Library {
+}
 
 pub struct FreeType {
 	shader    gl.Shader
-	// use_ortho bool
 	width     int
 	height    int
 	vao       u32
@@ -89,8 +76,8 @@ mut:
 }
 
 struct C.Bitmap {
-	width int
-	rows int
+	width  int
+	rows   int
 	buffer int
 }
 
@@ -112,42 +99,43 @@ struct C.FT_Glyph_Metrics {
 }
 
 struct C.Glyph {
-	bitmap C.Bitmap
+	bitmap      C.Bitmap
 	bitmap_left int
-	bitmap_top int
-	advance Advance
-	metrics C.FT_Glyph_Metrics
+	bitmap_top  int
+	advance     Advance
+	metrics     C.FT_Glyph_Metrics
 }
 
 [typedef]
 struct C.FT_FaceRec {
-	glyph &C.Glyph
+	glyph       &C.Glyph
 	family_name charptr
-	style_name charptr
+	style_name  charptr
 }
-///type FT_Face &C.FT_FaceRec
 
+// /type FT_Face &C.FT_FaceRec
 fn C.FT_Load_Char(voidptr, i64, int) int
 
 fn ft_load_char(face &C.FT_FaceRec, code i64) Character {
-	//println('\nftload_char( code=$code)')
-	//C.printf('face=%p\n', face)
-	//C.printf('cobj=%p\n', _face.cobj)
-	ret := C.FT_Load_Char(face, code, C.FT_LOAD_RENDER|C.FT_LOAD_FORCE_AUTOHINT)
-	//println('ret=$ret')
+	// println('\nftload_char( code=$code)')
+	// C.printf('face=%p\n', face)
+	// C.printf('cobj=%p\n', _face.cobj)
+	ret := C.FT_Load_Char(face, code, C.FT_LOAD_RENDER | C.FT_LOAD_FORCE_AUTOHINT)
+	// println('ret=$ret')
 	if ret != 0 {
-		println('freetype: failed to load glyph (utf32 code=$code, ' +
-			'error code=$ret)')
-		return Character{code: code}
+		println('freetype: failed to load glyph (utf32 code=$code, ' + 'error code=$ret)')
+		return Character{
+			code: code
+	}
 	}
 	// Generate texture
 	mut texture := 0
 	C.glGenTextures(1, &texture)
 	C.glBindTexture(C.GL_TEXTURE_2D, texture)
 	fgwidth := (*face).glyph.bitmap.width
-	fgrows  := (*face).glyph.bitmap.rows
-	C.glTexImage2D(C.GL_TEXTURE_2D, 0, C.GL_RED, fgwidth,  fgrows,
-		0, C.GL_RED, C.GL_UNSIGNED_BYTE, (*face).glyph.bitmap.buffer)
+	fgrows := (*face).glyph.bitmap.rows
+	C.glTexImage2D(C.GL_TEXTURE_2D, 0, C.GL_RED, fgwidth, fgrows, 0, C.GL_RED, C.GL_UNSIGNED_BYTE,
+		(*face).glyph.bitmap.buffer)
 	// Set texture options
 	C.glTexParameteri(C.GL_TEXTURE_2D, C.GL_TEXTURE_WRAP_S, C.GL_CLAMP_TO_EDGE)
 	C.glTexParameteri(C.GL_TEXTURE_2D, C.GL_TEXTURE_WRAP_T, C.GL_CLAMP_TO_EDGE)
@@ -173,7 +161,9 @@ pub fn new_context(cfg gg.Cfg) &FreeType {
 	scale := cfg.scale
 	// Can only have text in ortho mode
 	if !cfg.use_ortho {
-		return &FreeType{face:0}
+		return &FreeType{
+			face: 0
+	}
 	}
 	width := cfg.width * scale
 	height := cfg.height * scale
@@ -193,7 +183,7 @@ pub fn new_context(cfg gg.Cfg) &FreeType {
 	C.glBlendFunc(C.GL_SRC_ALPHA, C.GL_ONE_MINUS_SRC_ALPHA)
 	shader := gl.new_shader('text')
 	shader.use()
-	projection := glm.ortho(0, width, 0, height)// 0 at BOT
+	projection := glm.ortho(0, width, 0, height) // 0 at BOT
 	shader.set_mat4('projection', projection)
 	// FREETYPE
 	ft := C.FT_Library{}
@@ -215,9 +205,11 @@ pub fn new_context(cfg gg.Cfg) &FreeType {
 		eprintln('freetype: font "$font_path" does not exist')
 		return 0
 	}
-	face := &C.FT_FaceRec{glyph:0}
+	face := &C.FT_FaceRec{
+		glyph: 0
+	}
 	ret = int(C.FT_New_Face(ft, font_path.str, 0, &face))
-	if ret != 0	{
+	if ret != 0 {
 		eprintln('freetype: failed to load font (error=$ret) from path: $font_path')
 		exit(1)
 	}
@@ -228,7 +220,7 @@ pub fn new_context(cfg gg.Cfg) &FreeType {
 	// Gen texture
 	// Load first 128 characters of ASCII set
 	mut chars := []Character{}
-	for c in 0..128 {
+	for c in 0 .. 128 {
 		ch := ft_load_char(face, i64(c))
 		// s := utf32_to_str(uint(0x043f))
 		// s := 'п'
@@ -240,10 +232,10 @@ pub fn new_context(cfg gg.Cfg) &FreeType {
 		// # ch = gg__ft_load_char(f, 0xd0bf) ;  // UTF 8
 		chars << ch
 	}
-	//ch := Character{}
+	// ch := Character{}
 	// Configure VAO
 	vao := gl.gen_vertex_array()
-	//println('new gg text context vao=$vao')
+	// println('new gg text context vao=$vao')
 	vbo := gl.gen_buffer()
 	gl.bind_vao(vao)
 	gl.bind_buffer(C.GL_ARRAY_BUFFER, vbo)
@@ -253,7 +245,7 @@ pub fn new_context(cfg gg.Cfg) &FreeType {
 	// # glVertexAttribPointer(0, 4, GL_FLOAT,false, 4 * sizeof(GLf32), 0);
 	// gl.bind_buffer(GL_ARRAY_BUFFER, uint(0))
 	// # glBindVertexArray(0);
-	ctx := &FreeType {
+	ctx := &FreeType{
 		shader: shader
 		width: width
 		height: height
@@ -263,21 +255,21 @@ pub fn new_context(cfg gg.Cfg) &FreeType {
 		chars: chars
 		face: face
 	}
-	//ctx.init_utf8_runes()
+	// ctx.init_utf8_runes()
 	return ctx
 }
 
-pub fn (ctx mut FreeType) draw_text(_x, _y int, text string, cfg gx.TextCfg) {
-	//utext := text.ustring_tmp()
+pub fn (mut ctx FreeType) draw_text(_x, _y int, text string, cfg gx.TextCfg) {
+	// utext := text.ustring_tmp()
 	utext := text.ustring()
 	ctx.private_draw_text(_x, _y, utext, cfg)
 }
 
-fn (ctx mut FreeType) draw_text_fast(_x, _y int, text ustring, cfg gx.TextCfg) {
+fn (mut ctx FreeType) draw_text_fast(_x, _y int, text ustring, cfg gx.TextCfg) {
 	ctx.private_draw_text(_x, _y, text, cfg)
 }
 
-fn (ctx mut FreeType) private_draw_text(_x, _y int, utext ustring, cfg gx.TextCfg) {
+fn (mut ctx FreeType) private_draw_text(_x, _y int, utext ustring, cfg gx.TextCfg) {
 	/*
 	if utext.s.contains('on_seg') {
 		println('\nat(0)')
@@ -295,14 +287,14 @@ fn (ctx mut FreeType) private_draw_text(_x, _y int, utext ustring, cfg gx.TextCf
 	yoffset := if ctx.scale > 1 { 5 } else { -1 } // 5 hidpi, -1 lowdpi
 	// println('scale=$ctx.scale size=$cfg.size')
 	if cfg.align == gx.ALIGN_RIGHT {
-		//width := utext.len * 7
+		// width := utext.len * 7
 		width := wx
 		x -= width + 10
 	}
 	x *= ctx.scale
 	y *= ctx.scale
 	y += yoffset
-	y = f32(ctx.height) - y //invert y direction
+	y = f32(ctx.height) - y // invert y direction
 	color := cfg.color
 	// Activate corresponding render state
 	ctx.shader.use()
@@ -311,25 +303,24 @@ fn (ctx mut FreeType) private_draw_text(_x, _y int, utext ustring, cfg gx.TextCf
 	gl.bind_vao(ctx.vao)
 	// Iterate through all characters
 	// utext := text.ustring()
-	for i in 0..utext.len {
-		_rune := utext.at(i)
-		// println('$i => $_rune')
+	for i in 0 .. utext.len {
+		rune_ := utext.at(i)
+		// println('$i => $rune_')
 		mut ch := Character{}
 		mut found := false
-		if _rune.len == 1 {
-			idx := _rune[0]
+		if rune_.len == 1 {
+			idx := rune_[0]
 			if idx < 0 || idx >= ctx.chars.len {
-				println('BADE RUNE $_rune')
+				println('BADE RUNE $rune_')
 				continue
 			}
 			found = true
-			ch = ctx.chars[_rune[0]]
-		}
-		else if _rune.len > 1 {
+			ch = ctx.chars[rune_[0]]
+		} else if rune_.len > 1 {
 			// TODO O(1) use map
-			for j in 0..ctx.utf_runes.len {
+			for j in 0 .. ctx.utf_runes.len {
 				rune_j := ctx.utf_runes[j]
-				if rune_j==_rune {
+				if rune_j == rune_ {
 					ch = ctx.utf_chars[j]
 					found = true
 					break
@@ -337,31 +328,30 @@ fn (ctx mut FreeType) private_draw_text(_x, _y int, utext ustring, cfg gx.TextCf
 			}
 		}
 		// A new Unicode character. Load it and cache it.
-		if !found && _rune.len > 0 && _rune[0] > 32 {
-			//c := _rune[0]
-			//println('cant draw rune "$_rune" code=$c, loading')
-			//continue
-			ch = ft_load_char(ctx.face, _rune.utf32_code())
-			//println('done loading')
-			ctx.utf_runes << _rune
+		if !found && rune_.len > 0 && rune_[0] > 32 {
+			// c := rune_[0]
+			// println('cant draw rune "$rune_" code=$c, loading')
+			// continue
+			ch = ft_load_char(ctx.face, rune_.utf32_code())
+			// println('done loading')
+			ctx.utf_runes << rune_
 			ctx.utf_chars << ch
-			//exit(1)
+			// exit(1)
 			// continue
 		}
 		xpos := x + f32(ch.horizontal_bearing_px.x) * 1
 		ypos := y - f32(ch.size.y + wy - ch.horizontal_bearing_px.y) * 1
-		//ypos := y - wy
+		// ypos := y - wy
 		w := f32(ch.size.x) * 1
 		h := f32(ch.size.y) * 1
 		// Update VBO for each character
-		vertices :=	[
-		 xpos,     ypos + h,   0.0, 0.0 ,
-		 xpos,     ypos,       0.0, 1.0 ,
-		 xpos + w, ypos,       1.0, 1.0 ,
-		 xpos,     ypos + h,   0.0, 0.0 ,
-		 xpos + w, ypos,       1.0, 1.0 ,
-		 xpos + w, ypos + h,   1.0, 0.0
-		]
+		vertices := [
+			xpos, ypos + h, 0.0, 0.0,
+			xpos, ypos, 0.0, 1.0,
+			xpos + w, ypos, 1.0, 1.0,
+			xpos, ypos + h, 0.0, 0.0,
+			xpos + w, ypos, 1.0, 1.0,
+			xpos + w, ypos + h, 1.0, 0.0]
 		// Render glyph texture over quad
 		C.glBindTexture(C.GL_TEXTURE_2D, ch.texture_id)
 		// Update content of VBO memory
@@ -372,9 +362,9 @@ fn (ctx mut FreeType) private_draw_text(_x, _y int, utext ustring, cfg gx.TextCf
 		gl.draw_arrays(C.GL_TRIANGLES, 0, 6)
 		x += f32(ch.horizontal_advance_px)
 		// Stop drawing if the limit is reached
-		if cfg.max_width > 0  {
+		if cfg.max_width > 0 {
 			if x >= cfg.max_width {
-				//break
+				// break
 			}
 		}
 	}
@@ -382,8 +372,8 @@ fn (ctx mut FreeType) private_draw_text(_x, _y int, utext ustring, cfg gx.TextCf
 	C.glBindTexture(C.GL_TEXTURE_2D, 0)
 }
 
-pub fn (ctx mut FreeType) draw_text_def(x, y int, text string) {
-	cfg := gx.TextCfg {
+pub fn (mut ctx FreeType) draw_text_def(x, y int, text string) {
+	cfg := gx.TextCfg{
 		color: gx.Black
 		size: default_font_size
 		align: gx.align_left
@@ -391,50 +381,49 @@ pub fn (ctx mut FreeType) draw_text_def(x, y int, text string) {
 	ctx.draw_text(x, y, text, cfg)
 }
 
-pub fn (ctx mut FreeType) text_width(s string) int {
+pub fn (mut ctx FreeType) text_width(s string) int {
 	x, _ := ctx.text_size(s)
 	return x
 }
 
-pub fn (ctx mut FreeType) text_height(s string) int {
+pub fn (mut ctx FreeType) text_height(s string) int {
 	_, y := ctx.text_size(s)
 	return y
 }
 
-pub fn (ctx mut FreeType) text_size(s string) (int, int) {
-	//t := time.ticks()
+pub fn (mut ctx FreeType) text_size(s string) (int, int) {
+	// t := time.ticks()
 	utext := s.ustring()
 	mut x := u32(0)
 	mut maxy := u32(0)
-	mut _rune := ''
+	mut rune_ := ''
 	mut ch := Character{}
-	for i in 0..utext.len {
-		_rune = utext.at(i)
+	for i in 0 .. utext.len {
+		rune_ = utext.at(i)
 		ch = Character{}
 		mut found := false
-		if _rune.len == 1 {
-			idx := _rune[0]
+		if rune_.len == 1 {
+			idx := rune_[0]
 			if idx < 0 || idx >= ctx.chars.len {
-				println('BADE RUNE $_rune')
+				println('BADE RUNE $rune_')
 				continue
 			}
 			found = true
-			ch = ctx.chars[_rune[0]]
-		}
-		else if _rune.len > 1 {
+			ch = ctx.chars[rune_[0]]
+		} else if rune_.len > 1 {
 			// TODO O(1) use map
-			for j in 0..ctx.utf_runes.len {
+			for j in 0 .. ctx.utf_runes.len {
 				rune_j := ctx.utf_runes[j]
-				if rune_j==_rune {
+				if rune_j == rune_ {
 					ch = ctx.utf_chars[j]
 					found = true
 					break
 				}
 			}
 		}
-		if !found && _rune.len > 0 && _rune[0] > 32 {
-			ch = ft_load_char(ctx.face, _rune.utf32_code())
-			ctx.utf_runes << _rune
+		if !found && rune_.len > 0 && rune_[0] > 32 {
+			ch = ft_load_char(ctx.face, rune_.utf32_code())
+			ctx.utf_runes << rune_
 			ctx.utf_chars << ch
 		}
 		x += ch.horizontal_advance_px
@@ -442,12 +431,12 @@ pub fn (ctx mut FreeType) text_size(s string) (int, int) {
 			maxy = ch.vertical_advance_px
 		}
 	}
-	//println('text width "$s" = ${time.ticks() - t} ms')
-	//scaled_x := x
-	//scaled_y := maxy
-	scaled_x := int(f64(x)/ctx.scale)
-	scaled_y := int(f64(maxy)/ctx.scale)
-	//println('text_size of "${s}" | x,y: $x,$maxy | scaled_x: ${scaled_x:3d} | scaled_y: ${scaled_y:3d} ')
+	// println('text width "$s" = ${time.ticks() - t} ms')
+	// scaled_x := x
+	// scaled_y := maxy
+	scaled_x := int(f64(x) / ctx.scale)
+	scaled_y := int(f64(maxy) / ctx.scale)
+	// println('text_size of "${s}" | x,y: $x,$maxy | scaled_x: ${scaled_x:3d} | scaled_y: ${scaled_y:3d} ')
 	return scaled_x, scaled_y
 }
 
@@ -456,7 +445,6 @@ pub fn (f FT_Face) str() string {
 	return 'FT_Face{ style_name: ${ptr_str(f.style_name)} family_name: ${ptr_str(f.family_name)} }'
 }
 */
-
 pub fn (ac []Character) str() string {
 	mut res := []string{}
 	for c in ac {
diff --git a/vlib/glfw/glfw.v b/vlib/glfw/glfw.v
index d32957694a..c68eeb66ec 100644
--- a/vlib/glfw/glfw.v
+++ b/vlib/glfw/glfw.v
@@ -122,7 +122,7 @@ pub:
 }
 
 // type clickpub fn pub fn (window * GLFWwindow, button, action, mods int)
-type clickpubfn fn (window voidptr, button, action, mods int)
+type ClickPubFn fn (window voidptr, button, action, mods int)
 
 /*
  * TODO broken
diff --git a/vlib/net/ftp/ftp.v b/vlib/net/ftp/ftp.v
index c7a8a639f2..1c43f80bb6 100644
--- a/vlib/net/ftp/ftp.v
+++ b/vlib/net/ftp/ftp.v
@@ -1,5 +1,5 @@
 /*
-	basic ftp module
+basic ftp module
 	RFC-959
 	https://tools.ietf.org/html/rfc959
 
@@ -15,29 +15,28 @@
 	dtp.close()
 	ftp.close()
 */
-
 module ftp
 
 import net
 
 const (
-	Connected = 220
-	SpecifyPassword = 331
-	LoggedIn = 230
-	LoginFirst = 503
-	Anonymous = 530
-	OpenDataConnection = 150
+	Connected           = 220
+	SpecifyPassword     = 331
+	LoggedIn            = 230
+	LoginFirst          = 503
+	Anonymous           = 530
+	OpenDataConnection  = 150
 	CloseDataConnection = 226
-	CommandOk = 200
-	denied = 550
-	PassiveMode = 227
-	complete = 226
+	CommandOk           = 200
+	denied              = 550
+	PassiveMode         = 227
+	complete            = 226
 )
 
 struct DTP {
 mut:
 	sock net.Socket
-	ip string
+	ip   string
 	port int
 }
 
@@ -45,24 +44,27 @@ fn (dtp DTP) read() []byte {
 	mut data := []byte{}
 	for {
 		buf, len := dtp.sock.recv(1024)
-		if len == 0 { break }
-
-		for i in 0..len {
+		if len == 0 {
+			break
+		}
+		for i in 0 .. len {
 			data << buf[i]
 		}
-		unsafe { free(buf) }
+		unsafe {
+			free(buf)
+		}
 	}
-
 	return data
 }
 
 fn (dtp DTP) close() {
-	dtp.sock.close() or {}
+	dtp.sock.close() or {
+	}
 }
 
 struct FTP {
 mut:
-	sock net.Socket
+	sock        net.Socket
 	buffer_size int
 }
 
@@ -87,11 +89,9 @@ fn (ftp FTP) read() (int, string) {
 	$if debug {
 		println('FTP.v <<< $data')
 	}
-
 	if data.len < 5 {
 		return 0, ''
 	}
-
 	code := data[..3].int()
 	if data[3] == `-` {
 		for {
@@ -101,21 +101,18 @@ fn (ftp FTP) read() (int, string) {
 			}
 		}
 	}
-
 	return code, data
 }
 
-pub fn (ftp mut FTP) connect(ip string) bool {
+pub fn (mut ftp FTP) connect(ip string) bool {
 	sock := net.dial(ip, 21) or {
 		return false
 	}
 	ftp.sock = sock
-
 	code, _ := ftp.read()
 	if code == Connected {
 		return true
 	}
-
 	return false
 }
 
@@ -126,36 +123,34 @@ pub fn (ftp FTP) login(user, passwd string) bool {
 		}
 		return false
 	}
-
 	mut code, data := ftp.read()
 	if code == LoggedIn {
 		return true
 	}
-
 	if code != SpecifyPassword {
 		return false
 	}
-
 	ftp.write('PASS $passwd') or {
 		$if debug {
 			println('ERROR sending password')
 		}
 		return false
 	}
-
 	code, data = ftp.read()
-
+	// TODO Replace `data` with `_`
+	_ := data
 	if code == LoggedIn {
 		return true
 	}
-
 	return false
 }
 
 pub fn (ftp FTP) close() {
 	send_quit := 'QUIT\r\n'
-	ftp.sock.send_string(send_quit) or {}
-	ftp.sock.close() or {}
+	ftp.sock.send_string(send_quit) or {
+	}
+	ftp.sock.close() or {
+	}
 }
 
 pub fn (ftp FTP) pwd() string {
@@ -171,7 +166,9 @@ pub fn (ftp FTP) pwd() string {
 }
 
 pub fn (ftp FTP) cd(dir string) {
-	ftp.write('CWD $dir') or { return }
+	ftp.write('CWD $dir') or {
+		return
+	}
 	mut code, mut data := ftp.read()
 	match int(code) {
 		denied {
@@ -184,7 +181,6 @@ pub fn (ftp FTP) cd(dir string) {
 		}
 		else {}
 	}
-
 	$if debug {
 		println('CD $data')
 	}
@@ -194,14 +190,11 @@ fn new_dtp(msg string) ?DTP {
 	if !is_dtp_message_valid(msg) {
 		return error('Bad message')
 	}
-
 	ip, port := get_host_ip_from_dtp_message(msg)
-
 	sock := net.dial(ip, port) or {
 		return error('Cannot connect to the data channel')
 	}
-
-	dtp := DTP {
+	dtp := DTP{
 		sock: sock
 		ip: ip
 		port: port
@@ -210,18 +203,17 @@ fn new_dtp(msg string) ?DTP {
 }
 
 fn (ftp FTP) pasv() ?DTP {
-	ftp.write('PASV') or {}
+	ftp.write('PASV') or {
+	}
 	code, data := ftp.read()
 	$if debug {
 		println('pass: $data')
 	}
-
 	if code != PassiveMode {
 		return error('pasive mode not allowed')
 	}
-
 	dtp := new_dtp(data) or {
-	   return error(err)
+		return error(err)
 	}
 	return dtp
 }
@@ -230,8 +222,8 @@ pub fn (ftp FTP) dir() ?[]string {
 	dtp := ftp.pasv() or {
 		return error('cannot establish data connection')
 	}
-
-	ftp.write('LIST') or {}
+	ftp.write('LIST') or {
+	}
 	code, _ := ftp.read()
 	if code == denied {
 		return error('LIST denied')
@@ -239,23 +231,20 @@ pub fn (ftp FTP) dir() ?[]string {
 	if code != OpenDataConnection {
 		return error('data channel empty')
 	}
-
 	list_dir := dtp.read()
 	result, _ := ftp.read()
 	if result != CloseDataConnection {
 		println('LIST not ok')
 	}
 	dtp.close()
-
 	mut dir := []string{}
 	sdir := string(byteptr(list_dir.data))
 	for lfile in sdir.split('\n') {
-		if lfile.len >1 {
+		if lfile.len > 1 {
 			spl := lfile.split(' ')
-			dir << spl[spl.len-1]
+			dir << spl[spl.len - 1]
 		}
 	}
-
 	return dir
 }
 
@@ -263,21 +252,17 @@ pub fn (ftp FTP) get(file string) ?[]byte {
 	dtp := ftp.pasv() or {
 		return error('Cannot stablish data connection')
 	}
-
-	ftp.write('RETR $file') or {}
+	ftp.write('RETR $file') or {
+	}
 	code, _ := ftp.read()
-
 	if code == denied {
 		return error('Permission denied')
 	}
-
 	if code != OpenDataConnection {
 		return error('Data connection not ready')
 	}
-
 	blob := dtp.read()
 	dtp.close()
-
 	return blob
 }
 
@@ -290,7 +275,6 @@ fn is_dtp_message_valid(msg string) bool {
 fn get_host_ip_from_dtp_message(msg string) (string, int) {
 	mut par_start_idx := -1
 	mut par_end_idx := -1
-
 	for i, c in msg {
 		if c == `(` {
 			par_start_idx = i + 1
@@ -299,9 +283,7 @@ fn get_host_ip_from_dtp_message(msg string) (string, int) {
 		}
 	}
 	data := msg[par_start_idx..par_end_idx].split(',')
-
 	ip := data[0..4].join('.')
 	port := data[4].int() * 256 + data[5].int()
-
 	return ip, port
 }
diff --git a/vlib/net/http/cookie.v b/vlib/net/http/cookie.v
index 3ca1654868..d245779866 100644
--- a/vlib/net/http/cookie.v
+++ b/vlib/net/http/cookie.v
@@ -57,11 +57,11 @@ pub fn read_set_cookies(h map[string][]string) []&Cookie {
 			continue
 		}
 		name := keyval[0]
-		_value := keyval[1]
+		raw_value := keyval[1]
 		if !is_cookie_name_valid(name) {
 			continue
 		}
-		value := parse_cookie_value(_value, true) or {
+		value := parse_cookie_value(raw_value, true) or {
 			continue
 		}
 		mut c  := &Cookie{
@@ -75,14 +75,14 @@ pub fn read_set_cookies(h map[string][]string) []&Cookie {
 				continue
 			}
 			mut attr := parts[i]
-			mut _val := ''
+			mut raw_val := ''
 			if attr.contains('=') {
 				pieces := attr.split('=')
 				attr = pieces[0]
-				_val = pieces[1]
+				raw_val = pieces[1]
 			}
 			lower_attr := attr.to_lower()
-			val := parse_cookie_value(_val, false) or {
+			val := parse_cookie_value(raw_val, false) or {
 				c.unparsed << parts[i]
 				continue
 			}
@@ -158,9 +158,9 @@ pub fn read_cookies(h map[string][]string, filter string) []&Cookie {
 		mut part := ''
 		for line.len > 0 {
 			if line.index_any(';') > 0 {
-				_parts := line.split(';')
-				part = _parts[0]
-				line = _parts[1]
+				line_parts := line.split(';')
+				part = line_parts[0]
+				line = line_parts[1]
 			} else {
 				part = line
 				line = ''
@@ -172,9 +172,9 @@ pub fn read_cookies(h map[string][]string, filter string) []&Cookie {
 			mut name := part
 			mut val := ''
 			if part.contains('=') {
-				_parts := part.split('=')
-				name = _parts[0]
-				val = _parts[1]
+				val_parts := part.split('=')
+				name = val_parts[0]
+				val = val_parts[1]
 			}
 			if !is_cookie_name_valid(name) {
 				continue
@@ -182,12 +182,9 @@ pub fn read_cookies(h map[string][]string, filter string) []&Cookie {
 			if filter != '' && filter != name {
 				continue
 			}
-			 // Circumvent the issue with assigning an `or` expression to an existing value
-			 // TODO: Fix when fixed in compiler
-			_val := parse_cookie_value(val, true) or {
+			val = parse_cookie_value(val, true) or {
 				continue
 			}
-			val = _val
 			cookies << &Cookie{name: name, value: val}
 		}
 	}
diff --git a/vlib/net/http/download_nix.c.v b/vlib/net/http/download_nix.c.v
index c7ddbad1cc..ee648ccc7d 100644
--- a/vlib/net/http/download_nix.c.v
+++ b/vlib/net/http/download_nix.c.v
@@ -3,13 +3,14 @@
 // that can be found in the LICENSE file.
 module http
 
-type downloadfn fn(written int)type download_finished_fn fn()
+type DownloadFn = fn (written int)
+
 /*
 struct DownloadStruct {
 mut:
 	stream  voidptr
 	written int
-	cb      downloadfn
+	cb      DownloadFn
 }
 */
 fn download_cb(ptr voidptr, size, nmemb size_t, userp voidptr) {
@@ -23,7 +24,7 @@ fn download_cb(ptr voidptr, size, nmemb size_t, userp voidptr) {
 */
 }
 
-pub fn download_file_with_progress(url, out string, cb downloadfn, cb_finished fn()) {
+pub fn download_file_with_progress(url, out string, cb DownloadFn, cb_finished fn()) {
 	/*
 	curl := C.curl_easy_init()
 	if isnil(curl) {
@@ -49,4 +50,3 @@ pub fn download_file_with_progress(url, out string, cb downloadfn, cb_finished f
 
 fn empty() {
 }
-
diff --git a/vlib/net/http/http.v b/vlib/net/http/http.v
index 17075d9081..5ed27c8ff6 100644
--- a/vlib/net/http/http.v
+++ b/vlib/net/http/http.v
@@ -7,7 +7,7 @@ import net.urllib
 import net.http.chunked
 
 const (
-	max_redirects = 4
+	max_redirects        = 4
 	content_type_default = 'text/plain'
 )
 
@@ -20,7 +20,6 @@ pub mut:
 	url        string
 	user_agent string
 	verbose    bool
-//mut:
 	user_ptr   voidptr
 	ws_func    voidptr
 }
@@ -32,8 +31,8 @@ pub mut:
 	params     map[string]string
 	headers    map[string]string
 	cookies    map[string]string
-	user_agent string//='v' QTODO
-	verbose    bool=false
+	user_agent string // ='v' QTODO
+	verbose    bool = false
 }
 
 pub struct Response {
@@ -44,9 +43,9 @@ pub:
 	status_code int
 }
 
-pub fn new_request(method, url_, data string) ?Request{
+pub fn new_request(method, url_, data string) ?Request {
 	url := if method == 'GET' { url_ + '?' + data } else { url_ }
-	//println('new req() method=$method url="$url" dta="$data"')
+	// println('new req() method=$method url="$url" dta="$data"')
 	return Request{
 		method: method.to_upper()
 		url: url
@@ -147,7 +146,7 @@ pub fn url_encode_form_data(data map[string]string) string {
 	return pieces.join('&')
 }
 
-fn fetch_with_method(method string, url string, _config FetchConfig) ?Response {
+fn fetch_with_method(method, url string, _config FetchConfig) ?Response {
 	mut config := _config
 	config.method = method
 	return fetch(url, config)
@@ -173,21 +172,21 @@ fn build_url_from_fetch(_url string, config FetchConfig) ?string {
 	return url.str()
 }
 
-fn (req mut Request) free() {
+fn (mut req Request) free() {
 	req.headers.free()
 }
 
-fn (resp mut Response) free() {
+fn (mut resp Response) free() {
 	resp.headers.free()
 }
 
 // add_header adds the key and value of an HTTP request header
-pub fn (req mut Request) add_header(key, val string) {
+pub fn (mut req Request) add_header(key, val string) {
 	req.headers[key] = val
 }
 
 pub fn parse_headers(lines []string) map[string]string {
-	mut headers := map[string]string
+	mut headers := map[string]string{}
 	for i, line in lines {
 		if i == 0 {
 			continue
@@ -258,8 +257,7 @@ fn (req &Request) method_and_url_to_response(method string, url urllib.URL) ?Res
 			return error(err)
 		}
 		return res
-	}
-	else if scheme == 'http' {
+	} else if scheme == 'http' {
 		// println('http_do( $nport, $method, $host_name, $path )')
 		res := req.http_do(nport, method, host_name, path) or {
 			return error(err)
@@ -271,9 +269,9 @@ fn (req &Request) method_and_url_to_response(method string, url urllib.URL) ?Res
 
 fn parse_response(resp string) Response {
 	// TODO: Header data type
-	mut headers := map[string]string
+	mut headers := map[string]string{}
 	// TODO: Cookie data type
-	mut cookies := map[string]string
+	mut cookies := map[string]string{}
 	first_header := resp.all_before('\n')
 	mut status_code := 0
 	if first_header.contains('HTTP/') {
@@ -341,7 +339,8 @@ fn (req &Request) build_request_headers(method, host_name, path string) string {
 		uheaders << '${key}: ${val}\r\n'
 	}
 	uheaders << req.build_request_cookies_header()
-	return '$method $path HTTP/1.1\r\n' + uheaders.join('') + 'Connection: close\r\n\r\n' + req.data
+	return '$method $path HTTP/1.1\r\n' + uheaders.join('') + 'Connection: close\r\n\r\n' +
+		req.data
 }
 
 fn (req &Request) build_request_cookies_header() string {
@@ -373,5 +372,3 @@ pub fn unescape(s string) string {
 pub fn escape(s string) string {
 	panic('http.escape() was replaced with http.escape_url()')
 }
-
-type wsfn fn(s string, ptr voidptr)
diff --git a/vlib/net/init_windows.c.v b/vlib/net/init_windows.c.v
index 7c6e090a9d..5066d83c43 100644
--- a/vlib/net/init_windows.c.v
+++ b/vlib/net/init_windows.c.v
@@ -7,7 +7,7 @@ module net
 struct C.WSAData {
 mut:
 	wVersion u16
-	wHighVersion u16	
+	wHighVersion u16
 	szDescription [257]byte
 	szSystemStatus [129]byte
 	iMaxSockets u16
diff --git a/vlib/net/socket.v b/vlib/net/socket.v
index 2a1c77bad6..25810136f8 100644
--- a/vlib/net/socket.v
+++ b/vlib/net/socket.v
@@ -6,7 +6,7 @@ pub struct Socket {
 pub:
 	sockfd int
 	family int
-	_type  int
+	typ    int
 	proto  int
 }
 
@@ -39,53 +39,39 @@ struct C.sockaddr_storage {
 
 fn C.socket() int
 
-
 fn C.setsockopt() int
 
-
 fn C.htonl() int
 
-
 fn C.htons() int
 
-
 fn C.bind() int
 
-
 fn C.listen() int
 
-
 fn C.accept() int
 
-
 fn C.getaddrinfo() int
 
-
 fn C.connect() int
 
-
 fn C.send() int
 
-
 fn C.recv() int
 
-
 fn C.read() int
 
-
 fn C.shutdown() int
 
-
 fn C.close() int
 
-
 fn C.ntohs() int
 
-
 fn C.getsockname() int
+
 // create socket
-pub fn new_socket(family int, _type int, proto int) ?Socket {
-	sockfd := C.socket(family, _type, proto)
+pub fn new_socket(family, typ, proto int) ?Socket {
+	sockfd := C.socket(family, typ, proto)
 	one := 1
 	// This is needed so that there are no problems with reusing the
 	// same port after the application exits.
@@ -96,7 +82,7 @@ pub fn new_socket(family int, _type int, proto int) ?Socket {
 	s := Socket{
 		sockfd: sockfd
 		family: family
-		_type: _type
+		typ: typ
 		proto: proto
 	}
 	return s
@@ -107,7 +93,7 @@ pub fn socket_udp() ?Socket {
 }
 
 // set socket options
-pub fn (s Socket) setsockopt(level int, optname int, optvalue &int) ?int {
+pub fn (s Socket) setsockopt(level, optname int, optvalue &int) ?int {
 	res := C.setsockopt(s.sockfd, level, optname, optvalue, sizeof(&int))
 	if res < 0 {
 		return error('net.setsocketopt: failed with $res')
@@ -117,8 +103,7 @@ pub fn (s Socket) setsockopt(level int, optname int, optvalue &int) ?int {
 
 // bind socket to port
 pub fn (s Socket) bind(port int) ?int {
-	mut addr := C.sockaddr_in{
-	}
+	mut addr := C.sockaddr_in{}
 	addr.sin_family = s.family
 	addr.sin_port = C.htons(port)
 	addr.sin_addr.s_addr = C.htonl(C.INADDR_ANY)
@@ -178,8 +163,7 @@ pub fn (s Socket) accept() ?Socket {
 	$if debug {
 		println('accept()')
 	}
-	addr := C.sockaddr_storage{
-	}
+	addr := C.sockaddr_storage{}
 	size := 128 // sizeof(sockaddr_storage)
 	sockfd := C.accept(s.sockfd, &addr, &size)
 	if sockfd < 0 {
@@ -188,7 +172,7 @@ pub fn (s Socket) accept() ?Socket {
 	c := Socket{
 		sockfd: sockfd
 		family: s.family
-		_type: s._type
+		typ: s.typ
 		proto: s.proto
 	}
 	return c
@@ -196,10 +180,9 @@ pub fn (s Socket) accept() ?Socket {
 
 // connect to given addrress and port
 pub fn (s Socket) connect(address string, port int) ?int {
-	mut hints := C.addrinfo{
-	}
+	mut hints := C.addrinfo{}
 	hints.ai_family = s.family
-	hints.ai_socktype = s._type
+	hints.ai_socktype = s.typ
 	hints.ai_flags = C.AI_PASSIVE
 	hints.ai_protocol = s.proto
 	hints.ai_addrlen = 0
@@ -210,12 +193,12 @@ pub fn (s Socket) connect(address string, port int) ?int {
 	sport := '$port'
 	info_res := C.getaddrinfo(address.str, sport.str, &hints, &info)
 	if info_res != 0 {
-		error_message := os.get_error_msg(net.error_code())
+		error_message := os.get_error_msg(error_code())
 		return error('net.connect: getaddrinfo failed "$error_message"')
 	}
 	res := C.connect(s.sockfd, info.ai_addr, info.ai_addrlen)
 	if res < 0 {
-		error_message := os.get_error_msg(net.error_code())
+		error_message := os.get_error_msg(error_code())
 		return error('net.connect: connect failed "$error_message"')
 	}
 	return res
@@ -256,11 +239,13 @@ pub fn (s Socket) send_string(sdata string) ?int {
 }
 
 // receive string data from socket. NB: you are responsible for freeing the returned byteptr
-pub fn (s Socket) recv(bufsize int) (byteptr,int) {
+pub fn (s Socket) recv(bufsize int) (byteptr, int) {
 	mut buf := byteptr(0)
-	unsafe { buf = malloc(bufsize) }
+	unsafe {
+		buf = malloc(bufsize)
+	}
 	res := C.recv(s.sockfd, buf, bufsize, 0)
-	return buf,res
+	return buf, res
 }
 
 // TODO: remove cread/2 and crecv/2 when the Go net interface is done
@@ -300,10 +285,11 @@ pub fn (s Socket) close() ?int {
 }
 
 pub const (
-	CRLF = '\r\n'
+	CRLF     = '\r\n'
 	MAX_READ = 400
 	MSG_PEEK = 0x02
 )
+
 // write - write a string with CRLF after it over the socket s
 pub fn (s Socket) write(str string) ?int {
 	line := '$str$CRLF'
@@ -329,7 +315,7 @@ pub fn (s Socket) read_line() string {
 		}
 		buf[n] = `\0`
 		mut eol_idx := -1
-		for i in 0..n {
+		for i in 0 .. n {
 			if int(buf[i]) == `\n` {
 				eol_idx = i
 				// Ensure that tos_clone(buf) later,
@@ -377,8 +363,7 @@ pub fn (s Socket) read_all() string {
 }
 
 pub fn (s Socket) get_port() int {
-	mut addr := C.sockaddr_in{
-	}
+	mut addr := C.sockaddr_in{}
 	size := 16 // sizeof(sockaddr_in)
 	C.getsockname(s.sockfd, &addr, &size)
 	return C.ntohs(addr.sin_port)
diff --git a/vlib/os/os.v b/vlib/os/os.v
index 37275990b2..008f2cb578 100644
--- a/vlib/os/os.v
+++ b/vlib/os/os.v
@@ -148,9 +148,9 @@ fn C.CopyFile(&u32, &u32, int) int
 // TODO implement actual cp for linux
 pub fn cp(old, new string) ?bool {
 	$if windows {
-		_old := old.replace('/', '\\')
-		_new := new.replace('/', '\\')
-		C.CopyFile(_old.to_wide(), _new.to_wide(), false)
+		w_old := old.replace('/', '\\')
+		w_new := new.replace('/', '\\')
+		C.CopyFile(w_old.to_wide(), w_new.to_wide(), false)
 		result := C.GetLastError()
 		if result == 0 {
 			return true
@@ -954,8 +954,8 @@ pub fn dir_exists(path string) bool {
 // is_dir returns a boolean indicating whether the given path is a directory.
 pub fn is_dir(path string) bool {
 	$if windows {
-		_path := path.replace('/', '\\')
-		attr := C.GetFileAttributesW(_path.to_wide())
+		w_path := path.replace('/', '\\')
+		attr := C.GetFileAttributesW(w_path.to_wide())
 		if attr == u32(C.INVALID_FILE_ATTRIBUTES) {
 			return false
 		}
diff --git a/vlib/os/os_windows.c.v b/vlib/os/os_windows.c.v
index 6bb6be0795..48ba63e11d 100644
--- a/vlib/os/os_windows.c.v
+++ b/vlib/os/os_windows.c.v
@@ -16,64 +16,64 @@ pub type HANDLE voidptr
 // win: FILETIME
 // https://docs.microsoft.com/en-us/windows/win32/api/minwinbase/ns-minwinbase-filetime
 struct Filetime {
-  dwLowDateTime u32
-  dwHighDateTime u32
+  dw_low_date_time u32
+  dw_high_date_time u32
 }
 
 // win: WIN32_FIND_DATA
 // https://docs.microsoft.com/en-us/windows/win32/api/minwinbase/ns-minwinbase-_win32_find_dataw
 struct Win32finddata {
 mut:
-    dwFileAttributes u32
-    ftCreationTime Filetime
-  	ftLastAccessTime Filetime
-  	ftLastWriteTime Filetime
-	nFileSizeHigh u32
-	nFileSizeLow u32
-	dwReserved0 u32
-	dwReserved1 u32
-	cFileName [260]u16 // MAX_PATH = 260
-	cAlternateFileName [14]u16 // 14
-  	dwFileType u32
-  	dwCreatorType u32
-  	wFinderFlags u16
+    dw_file_attributes u32
+    ft_creation_time Filetime
+  	ft_last_access_time Filetime
+  	ft_last_write_time Filetime
+	n_file_size_high u32
+	n_file_size_low u32
+	dw_reserved0 u32
+	dw_reserved1 u32
+	c_file_name [260]u16 // MAX_PATH = 260
+	c_alternate_file_name [14]u16 // 14
+  	dw_file_type u32
+  	dw_creator_type u32
+  	w_finder_flags u16
 }
 
 struct ProcessInformation {
 mut:
-	hProcess voidptr
-	hThread voidptr
-	dwProcessId u32
-	dwThreadId u32
+	h_process voidptr
+	h_thread voidptr
+	dw_process_id u32
+	dw_thread_id u32
 }
 
 struct StartupInfo {
 mut:
 	cb u32
-	lpReserved &u16
-	lpDesktop &u16
-	lpTitle &u16
-	dwX u32
-	dwY u32
-	dwXSize u32
-	dwYSize u32
-	dwXCountChars u32
-	dwYCountChars u32
-	dwFillAttribute u32
-	dwFlags u32
-	wShowWindow u16
-	cbReserved2 u16
-	lpReserved2 byteptr
-	hStdInput voidptr
-	hStdOutput voidptr
-	hStdError voidptr
+	lp_reserved &u16
+	lp_desktop &u16
+	lp_title &u16
+	dw_x u32
+	dw_y u32
+	dw_x_size u32
+	dw_y_size u32
+	dw_x_count_chars u32
+	dw_y_count_chars u32
+	dw_fill_attributes u32
+	dw_flags u32
+	w_show_window u16
+	cb_reserved2 u16
+	lp_reserved2 byteptr
+	h_std_input voidptr
+	h_std_output voidptr
+	h_std_error voidptr
 }
 
 struct SecurityAttributes {
 mut:
-	nLength u32
-	lpSecurityDescriptor voidptr
-	bInheritHandle bool
+	n_length u32
+	lp_security_descriptor voidptr
+	b_inherit_handle bool
 }
 
 fn init_os_args_wide(argc int, argv &byteptr) []string {
@@ -102,12 +102,12 @@ pub fn ls(path string) ?[]string {
 	// NOTE:TODO: once we have a way to convert utf16 wide character to utf8
 	// we should use FindFirstFileW and FindNextFileW
 	h_find_files := C.FindFirstFile(path_files.to_wide(), voidptr(&find_file_data))
-	first_filename := string_from_wide(&u16(find_file_data.cFileName))
+	first_filename := string_from_wide(&u16(find_file_data.c_file_name))
 	if first_filename != '.' && first_filename != '..' {
 		dir_files << first_filename
 	}
 	for C.FindNextFile(h_find_files, voidptr(&find_file_data)) > 0 {
-		filename := string_from_wide(&u16(find_file_data.cFileName))
+		filename := string_from_wide(&u16(find_file_data.c_file_name))
 		if filename != '.' && filename != '..' {
 			dir_files << filename.clone()
 		}
@@ -186,12 +186,12 @@ pub fn mkdir(path string) ?bool {
 // get_file_handle retrieves the operating-system file handle that is associated with the specified file descriptor.
 pub fn get_file_handle(path string) HANDLE {
     mode := 'rb'
-    _fd := C._wfopen(path.to_wide(), mode.to_wide())
-    if _fd == 0 {
+    fd := C._wfopen(path.to_wide(), mode.to_wide())
+    if fd == 0 {
 	    return HANDLE(INVALID_HANDLE_VALUE)
     }
-    _handle := HANDLE(C._get_osfhandle(C._fileno(_fd))) // CreateFile? - hah, no -_-
-    return _handle
+    handle := HANDLE(C._get_osfhandle(C._fileno(fd))) // CreateFile? - hah, no -_-
+    return handle
 }
 
 // Ref - https://docs.microsoft.com/en-us/windows/win32/api/libloaderapi/nf-libloaderapi-getmodulefilenamea
@@ -205,8 +205,7 @@ pub fn get_module_filename(handle HANDLE) ?string {
 			status := int(C.GetModuleFileNameW(handle, voidptr(&buf), sz))
 			match status {
 				success {
-					_filename := string_from_wide2(buf, sz)
-					return _filename
+					return string_from_wide2(buf, sz)
 				}
 				else {
 					// Must handled with GetLastError and converted by FormatMessage
@@ -261,11 +260,11 @@ pub fn get_error_msg(code int) string {
     if code < 0 { // skip negative
         return ''
     }
-    _ptr_text := ptr_win_get_error_msg(u32(code))
-    if _ptr_text == 0 { // compare with null
+    ptr_text := ptr_win_get_error_msg(u32(code))
+    if ptr_text == 0 { // compare with null
         return ''
     }
-    return string_from_wide(_ptr_text)
+    return string_from_wide(ptr_text)
 }
 
 // exec starts the specified command, waits for it to complete, and returns its output.
@@ -277,8 +276,8 @@ pub fn exec(cmd string) ?Result {
 	mut child_stdout_read := &u32(0)
 	mut child_stdout_write := &u32(0)
 	mut sa := SecurityAttributes {}
-	sa.nLength = sizeof(C.SECURITY_ATTRIBUTES)
-	sa.bInheritHandle = true
+	sa.n_length = sizeof(C.SECURITY_ATTRIBUTES)
+	sa.b_inherit_handle = true
 
 	create_pipe_ok := C.CreatePipe(voidptr(&child_stdout_read),
 		voidptr(&child_stdout_write), voidptr(&sa), 0)
@@ -294,14 +293,14 @@ pub fn exec(cmd string) ?Result {
 
 	proc_info := ProcessInformation{}
 	start_info := StartupInfo{
-		lpReserved: 0
-		lpDesktop: 0
-		lpTitle: 0
+		lp_reserved: 0
+		lp_desktop: 0
+		lp_title: 0
 		cb: sizeof(C.PROCESS_INFORMATION)
-		hStdInput: child_stdin
-		hStdOutput: child_stdout_write
-		hStdError: child_stdout_write
-		dwFlags: u32(C.STARTF_USESTDHANDLES)
+		h_std_input: child_stdin
+		h_std_output: child_stdout_write
+		h_std_error: child_stdout_write
+		dw_flags: u32(C.STARTF_USESTDHANDLES)
 	}
 	command_line := [32768]u16
 	C.ExpandEnvironmentStringsW(cmd.to_wide(), voidptr(&command_line), 32768)
@@ -325,10 +324,10 @@ pub fn exec(cmd string) ?Result {
 	soutput := read_data.str().trim_space()
 	read_data.free()
 	exit_code := u32(0)
-	C.WaitForSingleObject(proc_info.hProcess, C.INFINITE)
-	C.GetExitCodeProcess(proc_info.hProcess, voidptr(&exit_code))
-	C.CloseHandle(proc_info.hProcess)
-	C.CloseHandle(proc_info.hThread)
+	C.WaitForSingleObject(proc_info.h_process, C.INFINITE)
+	C.GetExitCodeProcess(proc_info.h_process, voidptr(&exit_code))
+	C.CloseHandle(proc_info.h_process)
+	C.CloseHandle(proc_info.h_thread)
 	return Result {
 		output: soutput
 		exit_code: int(exit_code)
diff --git a/vlib/sync/pool.v b/vlib/sync/pool.v
index 7803bce9d5..e97f41357b 100644
--- a/vlib/sync/pool.v
+++ b/vlib/sync/pool.v
@@ -151,15 +151,13 @@ fn process_in_thread(pool mut PoolProcessor, task_id int) {
 //	return *(&T(pool.items[idx]))
 //}
 
-// TODO: the below is a hack, remove it when v2 &string() casting works again
-type mystring string
 // get_string_item - called by the worker callback.
 // It does not use generics so it does not mess up vfmt.
 // TODO: remove the need for this when vfmt becomes smarter.
 pub fn (pool &PoolProcessor) get_string_item(idx int) string {
    // return *(&string(pool.items[idx]))
    // TODO: the below is a hack, remove it when v2 casting works again
-   return &mystring( pool.items[idx] )
+   return &string( pool.items[idx] )
 }
 
 // get_int_item - called by the worker callback.
diff --git a/vlib/term/term_windows.c.v b/vlib/term/term_windows.c.v
index 2e45fa8698..08226d57b8 100644
--- a/vlib/term/term_windows.c.v
+++ b/vlib/term/term_windows.c.v
@@ -8,18 +8,18 @@ struct Coord {
 }
 
 struct SmallRect {
-	Left   i16
-	Top    i16
-	Right  i16
-	Bottom i16
+	left   i16
+	top    i16
+	right  i16
+	bottom i16
 }
 
 struct ConsoleScreenBufferInfo {
-	dwSize              Coord
-	dwCursorPosition    Coord
-	wAttributes         u16
-	srWindow            SmallRect
-	dwMaximumWindowSize Coord
+	dw_size                Coord
+	dw_cursor_position     Coord
+	w_attributes           u16
+	sr_window              SmallRect
+	dw_maximum_window_size Coord
 }
 
 fn C.GetConsoleScreenBufferInfo(handle os.HANDLE, info &ConsoleScreenBufferInfo) bool
@@ -28,13 +28,11 @@ fn C.GetConsoleScreenBufferInfo(handle os.HANDLE, info &ConsoleScreenBufferInfo)
 pub fn get_terminal_size() (int, int) {
 	if is_atty(1) > 0 && os.getenv('TERM') != 'dumb' {
 		info := ConsoleScreenBufferInfo{}
-
 		if C.GetConsoleScreenBufferInfo(C.GetStdHandle(C.STD_OUTPUT_HANDLE), &info) {
-			columns := int(info.srWindow.Right - info.srWindow.Left + 1)
-			rows := int(info.srWindow.Bottom - info.srWindow.Top + 1)
+			columns := int(info.sr_window.right - info.sr_window.left + 1)
+			rows := int(info.sr_window.bottom - info.sr_window.top + 1)
 			return columns, rows
 		}
 	}
-
 	return default_columns_size, default_rows_size
 }
diff --git a/vlib/v/ast/ast.v b/vlib/v/ast/ast.v
index bc17664c23..81d03fcce9 100644
--- a/vlib/v/ast/ast.v
+++ b/vlib/v/ast/ast.v
@@ -100,6 +100,7 @@ pub:
 	name       string
 	path       string
 	expr       Expr
+	pos        token.Position
 	is_skipped bool // module main can be skipped in single file programs
 }
 
@@ -295,6 +296,7 @@ pub:
 	name     string
 	expr     Expr
 	has_expr bool
+	pos      token.Position
 pub mut:
 	typ      table.Type
 }
diff --git a/vlib/v/checker/checker.v b/vlib/v/checker/checker.v
index d6814110c9..414aff90d3 100644
--- a/vlib/v/checker/checker.v
+++ b/vlib/v/checker/checker.v
@@ -175,15 +175,44 @@ fn (mut c Checker) check_file_in_main(file ast.File) bool {
 	return has_main_fn
 }
 
+fn (mut c Checker) check_valid_snake_case(name, identifier string, pos token.Position) {
+	if name[0] == `_` {
+		c.error('$identifier `$name` cannot start with `_`', pos)
+	}
+	if util.contains_capital(name) {
+		c.error('$identifier `$name` cannot contain uppercase letters, use snake_case instead',
+			pos)
+	}
+}
+
+fn stripped_name(name string) string {
+	idx := name.last_index('.') or {
+		-1
+	}
+	return name[(idx + 1)..]
+}
+
+fn (mut c Checker) check_valid_pascal_case(name, identifier string, pos token.Position) {
+	stripped_name := stripped_name(name)
+	if !stripped_name[0].is_capital() {
+		c.error('$identifier `$name` must begin with capital letter', pos)
+	}
+}
+
 pub fn (mut c Checker) type_decl(node ast.TypeDecl) {
 	match node {
 		ast.AliasTypeDecl {
+			// TODO Replace `c.file.mod.name != 'time'` by `it.is_c` once available
+			if c.file.mod.name != 'time' {
+				c.check_valid_pascal_case(it.name, 'type alias', it.pos)
+			}
 			typ_sym := c.table.get_type_symbol(it.parent_type)
 			if typ_sym.kind == .placeholder {
 				c.error("type `$typ_sym.name` doesn't exist", it.pos)
 			}
 		}
 		ast.FnTypeDecl {
+			c.check_valid_pascal_case(it.name, 'fn type', it.pos)
 			typ_sym := c.table.get_type_symbol(it.typ)
 			fn_typ_info := typ_sym.info as table.FnType
 			fn_info := fn_typ_info.func
@@ -199,6 +228,7 @@ pub fn (mut c Checker) type_decl(node ast.TypeDecl) {
 			}
 		}
 		ast.SumTypeDecl {
+			c.check_valid_pascal_case(it.name, 'sum type', it.pos)
 			for typ in it.sub_types {
 				typ_sym := c.table.get_type_symbol(typ)
 				if typ_sym.kind == .placeholder {
@@ -209,8 +239,21 @@ pub fn (mut c Checker) type_decl(node ast.TypeDecl) {
 	}
 }
 
+pub fn (mut c Checker) interface_decl(decl ast.InterfaceDecl) {
+	c.check_valid_pascal_case(decl.name, 'interface name', decl.pos)
+	for method in decl.methods {
+		c.check_valid_snake_case(method.name, 'method name', method.pos)
+	}
+}
+
 pub fn (mut c Checker) struct_decl(decl ast.StructDecl) {
+	if !decl.is_c && !c.is_builtin_mod {
+		c.check_valid_pascal_case(decl.name, 'struct name', decl.pos)
+	}
 	for i, field in decl.fields {
+		if !decl.is_c {
+			c.check_valid_snake_case(field.name, 'field name', field.pos)
+		}
 		for j in 0 .. i {
 			if field.name == decl.fields[j].name {
 				c.error('field name `$field.name` duplicate', field.pos)
@@ -1094,7 +1137,12 @@ pub fn (mut c Checker) return_stmt(mut return_stmt ast.Return) {
 }
 
 pub fn (mut c Checker) enum_decl(decl ast.EnumDecl) {
+	c.check_valid_pascal_case(decl.name, 'enum name', decl.pos)
 	for i, field in decl.fields {
+		if util.contains_capital(field.name) {
+			c.error('field name `$field.name` cannot contain uppercase letters, use snake_case instead',
+				field.pos)
+		}
 		for j in 0 .. i {
 			if field.name == decl.fields[j].name {
 				c.error('field name `$field.name` duplicate', field.pos)
@@ -1165,13 +1213,8 @@ pub fn (mut c Checker) assign_stmt(mut assign_stmt ast.AssignStmt) {
 		val_type := assign_stmt.right_types[i]
 		// check variable name for beginning with capital letter 'Abc'
 		is_decl := assign_stmt.op == .decl_assign
-		if is_decl && util.contains_capital(ident.name) {
-			c.error('variable names cannot contain uppercase letters, use snake_case instead',
-				ident.pos)
-		} else if is_decl && ident.kind != .blank_ident {
-			if ident.name.starts_with('__') {
-				c.error('variable names cannot start with `__`', ident.pos)
-			}
+		if is_decl && ident.name != '_' {
+			c.check_valid_snake_case(ident.name, 'variable name', ident.pos)
 		}
 		if assign_stmt.op == .decl_assign {
 			c.var_decl_name = ident.name
@@ -1385,6 +1428,7 @@ fn (mut c Checker) stmt(node ast.Stmt) {
 			mut field_names := []string{}
 			mut field_order := []int{}
 			for i, field in it.fields {
+				// TODO Check const name once the syntax is decided
 				if field.name in c.const_names {
 					c.error('field name `$field.name` duplicate', field.pos)
 				}
@@ -1433,6 +1477,9 @@ fn (mut c Checker) stmt(node ast.Stmt) {
 			c.check_expr_opt_call(it.expr, etype, false)
 		}
 		ast.FnDecl {
+			if !it.is_c && !c.is_builtin_mod {
+				c.check_valid_snake_case(it.name, 'function name', it.pos)
+			}
 			if it.is_method {
 				sym := c.table.get_type_symbol(it.receiver.typ)
 				if sym.kind == .interface_ {
@@ -1523,7 +1570,9 @@ fn (mut c Checker) stmt(node ast.Stmt) {
 			c.stmts(it.stmts)
 			c.in_for_count--
 		}
-		// ast.GlobalDecl {}
+		ast.GlobalDecl {
+			c.check_valid_snake_case(it.name, 'global name', it.pos)
+		}
 		ast.GoStmt {
 			if !(it.call_expr is ast.CallExpr) {
 				c.error('expression in `go` must be a function call', it.call_expr.position())
@@ -1533,19 +1582,12 @@ fn (mut c Checker) stmt(node ast.Stmt) {
 		// ast.HashStmt {}
 		ast.Import {}
 		ast.InterfaceDecl {
-			name := it.name.after('.')
-			if !name[0].is_capital() {
-				pos := token.Position{
-					line_nr: it.pos.line_nr
-					pos: it.pos.pos + 'interface'.len
-					len: name.len
-				}
-				c.error('interface name must begin with capital letter', pos)
-			}
+			c.interface_decl(it)
 		}
 		ast.Module {
 			c.mod = it.name
 			c.is_builtin_mod = it.name == 'builtin'
+			c.check_valid_snake_case(it.name, 'module name', it.pos)
 		}
 		ast.Return {
 			c.returns = true
@@ -1865,7 +1907,7 @@ pub fn (mut c Checker) ident(mut ident ast.Ident) table.Type {
 	return table.void_type
 }
 
-pub fn (mut c Checker) concat_expr(concat_expr mut ast.ConcatExpr) table.Type {
+pub fn (mut c Checker) concat_expr(mut concat_expr ast.ConcatExpr) table.Type {
 	mut mr_types := []table.Type{}
 	for expr in concat_expr.vals {
 		mr_types << c.expr(expr)
diff --git a/vlib/v/checker/checker_test.v b/vlib/v/checker/checker_test.v
index 626a2b2eb5..34d5c9c6b4 100644
--- a/vlib/v/checker/checker_test.v
+++ b/vlib/v/checker/checker_test.v
@@ -6,54 +6,59 @@ fn test_all() {
 	vexe := os.getenv('VEXE')
 	vroot := os.dir(vexe)
 	os.chdir(vroot)
-	dir := 'vlib/v/checker/tests'
+	classic_dir := 'vlib/v/checker/tests'
+	classic_tests := get_tests_in_dir(classic_dir)
+	global_dir := '$classic_dir/globals'
+	global_tests := get_tests_in_dir(global_dir)
+	// -prod so that warns are errors
+	total_errors += check_path(vexe, classic_dir, '-prod', '.out', classic_tests)
+	total_errors += check_path(vexe, global_dir, '--enable-globals', '.out', global_tests)
+	total_errors += check_path(vexe, classic_dir, '--enable-globals run', '.run.out', ['globals_error.vv'])
+	assert total_errors == 0
+}
+
+fn get_tests_in_dir(dir string) []string {
 	files := os.ls(dir) or {
 		panic(err)
 	}
 	mut tests := files.filter(it.ends_with('.vv'))
-	if tests.len == 0 {
-		println('no compiler tests found')
-		assert false
-	}
 	tests.sort()
-	for test in tests {
-		// -prod so that warns are errors
-		total_errors += check_path(vexe, dir, test, '-prod', '.out')
-	}
-	total_errors += check_path(vexe, dir, 'globals_error.vv', '--enable-globals run', '.run.out')
-	assert total_errors == 0
+	return tests
 }
 
-fn check_path(vexe, dir, test, voptions, result_extension string) int {
-	path := os.join_path(dir, test).replace('\\', '/')
-	program := path.replace('.vv', '.v')
-	print(program + ' ')
-	os.cp(path, program) or {
-		panic(err)
+fn check_path(vexe, dir, voptions, result_extension string, tests []string) int {
+	mut nb_fail := 0
+	for test in tests {
+		path := os.join_path(dir, test).replace('\\', '/')
+		program := path.replace('.vv', '.v')
+		print(program + ' ')
+		os.cp(path, program) or {
+			panic(err)
+		}
+		res := os.exec('$vexe $voptions $program') or {
+			panic(err)
+		}
+		mut expected := os.read_file(program.replace('.v', '') + result_extension) or {
+			panic(err)
+		}
+		expected = clean_line_endings(expected)
+		found := clean_line_endings(res.output)
+		if expected != found {
+			println(term.red('FAIL'))
+			println('============')
+			println('expected:')
+			println(expected)
+			println('============')
+			println('found:')
+			println(found)
+			println('============\n')
+			nb_fail += 1
+		} else {
+			println(term.green('OK'))
+			os.rm(program)
+		}
 	}
-	res := os.exec('$vexe $voptions $program') or {
-		panic(err)
-	}
-	mut expected := os.read_file(program.replace('.v', '') + result_extension) or {
-		panic(err)
-	}
-	expected = clean_line_endings(expected)
-	found := clean_line_endings(res.output)
-	if expected != found {
-		println(term.red('FAIL'))
-		println('============')
-		println('expected:')
-		println(expected)
-		println('============')
-		println('found:')
-		println(found)
-		println('============\n')
-		return 1
-	} else {
-		println(term.green('OK'))
-		os.rm(program)
-	}
-	return 0
+	return nb_fail
 }
 
 fn clean_line_endings(s string) string {
diff --git a/vlib/v/checker/tests/decl_underscore.out b/vlib/v/checker/tests/decl_underscore.out
deleted file mode 100644
index c947b28d25..0000000000
--- a/vlib/v/checker/tests/decl_underscore.out
+++ /dev/null
@@ -1,5 +0,0 @@
-vlib/v/checker/tests/decl_underscore.v:2:2: error: variable names cannot start with `__`
-    1 | fn main() {
-    2 |     __abc := 1
-      |     ~~~~~
-    3 | }
diff --git a/vlib/v/checker/tests/decl_underscore.vv b/vlib/v/checker/tests/decl_underscore.vv
deleted file mode 100644
index 6ef91ce0dc..0000000000
--- a/vlib/v/checker/tests/decl_underscore.vv
+++ /dev/null
@@ -1,3 +0,0 @@
-fn main() {
-	__abc := 1
-}
diff --git a/vlib/v/checker/tests/enum_field_name_err.out b/vlib/v/checker/tests/enum_field_name_err.out
deleted file mode 100644
index 51649b0b07..0000000000
--- a/vlib/v/checker/tests/enum_field_name_err.out
+++ /dev/null
@@ -1,6 +0,0 @@
-vlib/v/checker/tests/enum_field_name_err.v:2:5: error: field name `Green` must be all lowercase
-    1 | enum Color {
-    2 |     Green
-      |     ~~~~~
-    3 |     yellow
-    4 | }
diff --git a/vlib/v/checker/tests/enum_field_name_err.vv b/vlib/v/checker/tests/enum_field_name_err.vv
deleted file mode 100644
index 0ce39313d2..0000000000
--- a/vlib/v/checker/tests/enum_field_name_err.vv
+++ /dev/null
@@ -1,7 +0,0 @@
-enum Color {
-    Green
-    yellow
-}
-fn main(){
-	println('hello')
-}
diff --git a/vlib/v/checker/tests/enum_name_err.out b/vlib/v/checker/tests/enum_name_err.out
deleted file mode 100644
index 3322923ebd..0000000000
--- a/vlib/v/checker/tests/enum_name_err.out
+++ /dev/null
@@ -1,5 +0,0 @@
-vlib/v/checker/tests/enum_name_err.v:1:6: error: enum name `color` must begin with capital letter
-    1 | enum color {
-      |      ~~~~~
-    2 |     green
-    3 |     yellow
diff --git a/vlib/v/checker/tests/globals/incorrect_name_global.out b/vlib/v/checker/tests/globals/incorrect_name_global.out
new file mode 100644
index 0000000000..23d77899d3
--- /dev/null
+++ b/vlib/v/checker/tests/globals/incorrect_name_global.out
@@ -0,0 +1,3 @@
+vlib/v/checker/tests/globals/incorrect_name_global.v:1:1: error: global name `A` cannot contain uppercase letters, use snake_case instead
+    1 | __global A := 1
+      | ~~~~~~~~~~
\ No newline at end of file
diff --git a/vlib/v/checker/tests/globals/incorrect_name_global.vv b/vlib/v/checker/tests/globals/incorrect_name_global.vv
new file mode 100644
index 0000000000..253abc8c2d
--- /dev/null
+++ b/vlib/v/checker/tests/globals/incorrect_name_global.vv
@@ -0,0 +1 @@
+__global A := 1
diff --git a/vlib/v/checker/tests/incorrect_name_alias_type.out b/vlib/v/checker/tests/incorrect_name_alias_type.out
new file mode 100644
index 0000000000..93c4b780b5
--- /dev/null
+++ b/vlib/v/checker/tests/incorrect_name_alias_type.out
@@ -0,0 +1,3 @@
+vlib/v/checker/tests/incorrect_name_alias_type.v:1:1: error: type alias `integer` must begin with capital letter
+    1 | type integer = int
+      | ~~~~~~~~~~~~
\ No newline at end of file
diff --git a/vlib/v/checker/tests/incorrect_name_alias_type.vv b/vlib/v/checker/tests/incorrect_name_alias_type.vv
new file mode 100644
index 0000000000..7e2d3635c4
--- /dev/null
+++ b/vlib/v/checker/tests/incorrect_name_alias_type.vv
@@ -0,0 +1 @@
+type integer = int
diff --git a/vlib/v/checker/tests/incorrect_name_const.out b/vlib/v/checker/tests/incorrect_name_const.out
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/vlib/v/checker/tests/incorrect_name_const.vv b/vlib/v/checker/tests/incorrect_name_const.vv
new file mode 100644
index 0000000000..50f553f76d
--- /dev/null
+++ b/vlib/v/checker/tests/incorrect_name_const.vv
@@ -0,0 +1,3 @@
+const (
+	_my_const = 0
+)
diff --git a/vlib/v/checker/tests/incorrect_name_enum.out b/vlib/v/checker/tests/incorrect_name_enum.out
new file mode 100644
index 0000000000..8bb8f17e68
--- /dev/null
+++ b/vlib/v/checker/tests/incorrect_name_enum.out
@@ -0,0 +1,5 @@
+vlib/v/checker/tests/incorrect_name_enum.v:1:1: error: enum name `color` must begin with capital letter
+    1 | enum color {
+      | ~~~~~~~~~~
+    2 |     green
+    3 |     yellow
\ No newline at end of file
diff --git a/vlib/v/checker/tests/enum_name_err.vv b/vlib/v/checker/tests/incorrect_name_enum.vv
similarity index 53%
rename from vlib/v/checker/tests/enum_name_err.vv
rename to vlib/v/checker/tests/incorrect_name_enum.vv
index 9b08203569..90c4d4d571 100644
--- a/vlib/v/checker/tests/enum_name_err.vv
+++ b/vlib/v/checker/tests/incorrect_name_enum.vv
@@ -2,6 +2,3 @@ enum color {
     green
     yellow
 }
-fn main(){
-	println('hello')
-}
diff --git a/vlib/v/checker/tests/incorrect_name_enum_field.out b/vlib/v/checker/tests/incorrect_name_enum_field.out
new file mode 100644
index 0000000000..f2769ed11f
--- /dev/null
+++ b/vlib/v/checker/tests/incorrect_name_enum_field.out
@@ -0,0 +1,6 @@
+vlib/v/checker/tests/incorrect_name_enum_field.v:2:5: error: field name `Green` cannot contain uppercase letters, use snake_case instead
+    1 | enum Color {
+    2 |     Green
+      |     ~~~~~
+    3 |     red
+    4 |     blue
\ No newline at end of file
diff --git a/vlib/v/checker/tests/incorrect_name_enum_field.vv b/vlib/v/checker/tests/incorrect_name_enum_field.vv
new file mode 100644
index 0000000000..8cb00315f0
--- /dev/null
+++ b/vlib/v/checker/tests/incorrect_name_enum_field.vv
@@ -0,0 +1,5 @@
+enum Color {
+    Green
+    red
+    blue
+}
diff --git a/vlib/v/checker/tests/incorrect_name_fn_type.out b/vlib/v/checker/tests/incorrect_name_fn_type.out
new file mode 100644
index 0000000000..21e61cb154
--- /dev/null
+++ b/vlib/v/checker/tests/incorrect_name_fn_type.out
@@ -0,0 +1,3 @@
+vlib/v/checker/tests/incorrect_name_fn_type.v:1:1: error: fn type `callback` must begin with capital letter
+    1 | type callback = fn ()
+      | ~~~~~~~~~~~~~
diff --git a/vlib/v/checker/tests/incorrect_name_fn_type.vv b/vlib/v/checker/tests/incorrect_name_fn_type.vv
new file mode 100644
index 0000000000..f565315a36
--- /dev/null
+++ b/vlib/v/checker/tests/incorrect_name_fn_type.vv
@@ -0,0 +1 @@
+type callback = fn ()
diff --git a/vlib/v/checker/tests/incorrect_name_function.out b/vlib/v/checker/tests/incorrect_name_function.out
new file mode 100644
index 0000000000..f6c8faacde
--- /dev/null
+++ b/vlib/v/checker/tests/incorrect_name_function.out
@@ -0,0 +1,3 @@
+vlib/v/checker/tests/incorrect_name_function.v:1:1: error: function name `_my_fn` cannot start with `_`
+    1 | fn _my_fn() {}
+      | ~~~~~~~~~~~
\ No newline at end of file
diff --git a/vlib/v/checker/tests/incorrect_name_function.vv b/vlib/v/checker/tests/incorrect_name_function.vv
new file mode 100644
index 0000000000..b75a1a2bb3
--- /dev/null
+++ b/vlib/v/checker/tests/incorrect_name_function.vv
@@ -0,0 +1 @@
+fn _my_fn() {}
diff --git a/vlib/v/checker/tests/incorrect_name_interface.out b/vlib/v/checker/tests/incorrect_name_interface.out
new file mode 100644
index 0000000000..2a92ea8af7
--- /dev/null
+++ b/vlib/v/checker/tests/incorrect_name_interface.out
@@ -0,0 +1,3 @@
+vlib/v/checker/tests/incorrect_name_interface.v:1:1: error: interface name `_MyInterface` must begin with capital letter
+    1 | interface _MyInterface {}
+      | ~~~~~~~~~
\ No newline at end of file
diff --git a/vlib/v/checker/tests/incorrect_name_interface.vv b/vlib/v/checker/tests/incorrect_name_interface.vv
new file mode 100644
index 0000000000..abe6cb8ce3
--- /dev/null
+++ b/vlib/v/checker/tests/incorrect_name_interface.vv
@@ -0,0 +1 @@
+interface _MyInterface {}
diff --git a/vlib/v/checker/tests/incorrect_name_interface_method.out b/vlib/v/checker/tests/incorrect_name_interface_method.out
new file mode 100644
index 0000000000..b3e10e24f5
--- /dev/null
+++ b/vlib/v/checker/tests/incorrect_name_interface_method.out
@@ -0,0 +1,5 @@
+vlib/v/checker/tests/incorrect_name_interface_method.v:2:5: error: method name `_speak` cannot start with `_`
+    1 | interface MyInterface {
+    2 |     _speak()
+      |     ~~~~~~~~
+    3 | }
\ No newline at end of file
diff --git a/vlib/v/checker/tests/incorrect_name_interface_method.vv b/vlib/v/checker/tests/incorrect_name_interface_method.vv
new file mode 100644
index 0000000000..2ab12be632
--- /dev/null
+++ b/vlib/v/checker/tests/incorrect_name_interface_method.vv
@@ -0,0 +1,3 @@
+interface MyInterface {
+    _speak()
+}
diff --git a/vlib/v/checker/tests/incorrect_name_module.out b/vlib/v/checker/tests/incorrect_name_module.out
new file mode 100644
index 0000000000..3892aeb25f
--- /dev/null
+++ b/vlib/v/checker/tests/incorrect_name_module.out
@@ -0,0 +1,3 @@
+vlib/v/checker/tests/incorrect_name_module.v:1:1: error: module name `_A` cannot start with `_`
+    1 | module _A
+      | ~~~~~~~~~
\ No newline at end of file
diff --git a/vlib/v/checker/tests/incorrect_name_module.vv b/vlib/v/checker/tests/incorrect_name_module.vv
new file mode 100644
index 0000000000..50526ca647
--- /dev/null
+++ b/vlib/v/checker/tests/incorrect_name_module.vv
@@ -0,0 +1 @@
+module _A
diff --git a/vlib/v/checker/tests/incorrect_name_struct.out b/vlib/v/checker/tests/incorrect_name_struct.out
new file mode 100644
index 0000000000..057530babb
--- /dev/null
+++ b/vlib/v/checker/tests/incorrect_name_struct.out
@@ -0,0 +1,3 @@
+vlib/v/checker/tests/incorrect_name_struct.v:1:8: error: struct name `abc` must begin with capital letter
+    1 | struct abc {}
+      |        ~~~
\ No newline at end of file
diff --git a/vlib/v/checker/tests/incorrect_name_struct.vv b/vlib/v/checker/tests/incorrect_name_struct.vv
new file mode 100644
index 0000000000..0c77ebc7da
--- /dev/null
+++ b/vlib/v/checker/tests/incorrect_name_struct.vv
@@ -0,0 +1 @@
+struct abc {}
diff --git a/vlib/v/checker/tests/incorrect_name_struct_field.out b/vlib/v/checker/tests/incorrect_name_struct_field.out
new file mode 100644
index 0000000000..91c0a65649
--- /dev/null
+++ b/vlib/v/checker/tests/incorrect_name_struct_field.out
@@ -0,0 +1,5 @@
+vlib/v/checker/tests/incorrect_name_struct_field.v:2:5: error: field name `_a` cannot start with `_`
+    1 | struct Abc {
+    2 |     _a int
+      |     ~~~~~~
+    3 | }
\ No newline at end of file
diff --git a/vlib/v/checker/tests/incorrect_name_struct_field.vv b/vlib/v/checker/tests/incorrect_name_struct_field.vv
new file mode 100644
index 0000000000..b1b2205df4
--- /dev/null
+++ b/vlib/v/checker/tests/incorrect_name_struct_field.vv
@@ -0,0 +1,3 @@
+struct Abc {
+    _a int
+}
diff --git a/vlib/v/checker/tests/incorrect_name_sum_type.out b/vlib/v/checker/tests/incorrect_name_sum_type.out
new file mode 100644
index 0000000000..1288b7ca06
--- /dev/null
+++ b/vlib/v/checker/tests/incorrect_name_sum_type.out
@@ -0,0 +1,3 @@
+vlib/v/checker/tests/incorrect_name_sum_type.v:1:1: error: sum type `integer` must begin with capital letter
+    1 | type integer = i8 | i16 | int | i64
+      | ~~~~~~~~~~~~
\ No newline at end of file
diff --git a/vlib/v/checker/tests/incorrect_name_sum_type.vv b/vlib/v/checker/tests/incorrect_name_sum_type.vv
new file mode 100644
index 0000000000..8a3098fec8
--- /dev/null
+++ b/vlib/v/checker/tests/incorrect_name_sum_type.vv
@@ -0,0 +1 @@
+type integer = i8 | i16 | int | i64
diff --git a/vlib/v/checker/tests/incorrect_name_variable.out b/vlib/v/checker/tests/incorrect_name_variable.out
new file mode 100644
index 0000000000..87d31f561e
--- /dev/null
+++ b/vlib/v/checker/tests/incorrect_name_variable.out
@@ -0,0 +1,6 @@
+vlib/v/checker/tests/incorrect_name_variable.v:2:2: error: variable name `_abc` cannot start with `_`
+    1 | fn main() {
+    2 |     _abc := 1
+      |     ~~~~
+    3 |     _ := _abc
+    4 | }
\ No newline at end of file
diff --git a/vlib/v/checker/tests/incorrect_name_variable.vv b/vlib/v/checker/tests/incorrect_name_variable.vv
new file mode 100644
index 0000000000..dbbb549aeb
--- /dev/null
+++ b/vlib/v/checker/tests/incorrect_name_variable.vv
@@ -0,0 +1,4 @@
+fn main() {
+	_abc := 1
+	_ := _abc
+}
diff --git a/vlib/v/checker/tests/struct_field_name_duplicate_err.out b/vlib/v/checker/tests/struct_field_name_duplicate_err.out
index f25782b178..78b3ac23ba 100644
--- a/vlib/v/checker/tests/struct_field_name_duplicate_err.out
+++ b/vlib/v/checker/tests/struct_field_name_duplicate_err.out
@@ -1,7 +1,6 @@
-vlib/v/checker/tests/struct_field_name_duplicate_err.v:3:4: error: field name `a` duplicate
+vlib/v/checker/tests/struct_field_name_duplicate_err.v:3:2: error: field name `a` duplicate
     1 | struct A {
     2 |     a int
     3 |     a string
-      |       ~~~~~~
-    4 | }
-    5 | fn main(){}
+      |     ~~~~~~~~
+    4 | }
\ No newline at end of file
diff --git a/vlib/v/checker/tests/struct_field_name_duplicate_err.vv b/vlib/v/checker/tests/struct_field_name_duplicate_err.vv
index e59e586300..e1a30cb8a4 100644
--- a/vlib/v/checker/tests/struct_field_name_duplicate_err.vv
+++ b/vlib/v/checker/tests/struct_field_name_duplicate_err.vv
@@ -2,4 +2,3 @@ struct A {
 	a int
 	a string
 }
-fn main(){}
diff --git a/vlib/v/checker/tests/struct_name.out b/vlib/v/checker/tests/struct_name.out
deleted file mode 100644
index 78b2aa51a6..0000000000
--- a/vlib/v/checker/tests/struct_name.out
+++ /dev/null
@@ -1,5 +0,0 @@
-vlib/v/checker/tests/struct_name.v:1:8: error: struct name `abc` must begin with capital letter
-    1 | struct abc {
-      |        ~~~
-    2 |
-    3 | }
diff --git a/vlib/v/checker/tests/struct_name.vv b/vlib/v/checker/tests/struct_name.vv
deleted file mode 100644
index 4cd9b723b8..0000000000
--- a/vlib/v/checker/tests/struct_name.vv
+++ /dev/null
@@ -1,5 +0,0 @@
-struct abc {
-
-}
-
-fn main(){}
diff --git a/vlib/v/gen/cgen.v b/vlib/v/gen/cgen.v
index 3875bb1d5b..8b0437df4d 100644
--- a/vlib/v/gen/cgen.v
+++ b/vlib/v/gen/cgen.v
@@ -468,7 +468,7 @@ pub fn (mut g Gen) writeln(s string) {
 
 pub fn (mut g Gen) new_tmp_var() string {
 	g.tmp_count++
-	return 'tmp$g.tmp_count'
+	return '_t$g.tmp_count'
 }
 
 pub fn (mut g Gen) reset_tmp_count() {
@@ -1860,7 +1860,6 @@ fn (mut g Gen) concat_expr(node ast.ConcatExpr) {
 	styp := g.typ(node.return_type)
 	sym := g.table.get_type_symbol(node.return_type)
 	is_multi := sym.kind == .multi_return
-
 	if !is_multi {
 		g.expr(node.vals[0])
 	} else {
diff --git a/vlib/v/parser/parser.v b/vlib/v/parser/parser.v
index e62a64f1c7..7550deee3f 100644
--- a/vlib/v/parser/parser.v
+++ b/vlib/v/parser/parser.v
@@ -294,10 +294,9 @@ fn (mut p Parser) check_js_name() string {
 		p.next() // .name
 		p.next() // .dot
 	}
- 	// last .name
- 	name += p.tok.lit
+	// last .name
+	name += p.tok.lit
 	p.next()
-
 	return name
 }
 
@@ -462,8 +461,8 @@ pub fn (mut p Parser) stmt() ast.Stmt {
 				}
 			} else if p.peek_tok.kind == .name {
 				p.error_with_pos('unexpected name `$p.peek_tok.lit`', p.peek_tok.position())
-			} else if !p.inside_if_expr && !p.inside_match_body &&
-					!p.inside_or_expr && p.peek_tok.kind in [.rcbr, .eof] {
+			} else if !p.inside_if_expr && !p.inside_match_body && !p.inside_or_expr && p.peek_tok.kind in
+				[.rcbr, .eof] {
 				p.error_with_pos('`$p.tok.lit` evaluated but not used', p.tok.position())
 			}
 			epos := p.tok.position()
@@ -528,7 +527,8 @@ pub fn (mut p Parser) stmt() ast.Stmt {
 			}
 		}
 		.key_const {
-			p.error_with_pos('const can only be defined at the top level (outside of functions)', p.tok.position())
+			p.error_with_pos('const can only be defined at the top level (outside of functions)',
+				p.tok.position())
 		}
 		else {
 			return p.parse_comma_separated()
@@ -680,7 +680,7 @@ fn (mut p Parser) parse_comma_separated() ast.Stmt {
 			}
 		}
 		return ast.ExprStmt{
-			expr: ast.ConcatExpr {
+			expr: ast.ConcatExpr{
 				vals: collected
 			}
 			pos: p.tok.position()
@@ -706,7 +706,7 @@ pub fn (mut p Parser) parse_ident(is_c, is_js bool) ast.Ident {
 				name: '_'
 				kind: .blank_ident
 				pos: pos
-				info: ast.IdentVar {
+				info: ast.IdentVar{
 					is_mut: false
 					is_static: false
 				}
@@ -862,7 +862,7 @@ pub fn (mut p Parser) name_expr() ast.Expr {
 	} else if p.peek_tok.kind == .colon && p.prev_tok.kind != .str_dollar {
 		// `foo(key:val, key2:val2)`
 		return p.struct_init(true) // short_syntax:true
-	// JS. function call with more than 1 dot
+		// JS. function call with more than 1 dot
 	} else if is_js && p.peek_tok.kind == .dot && p.peek_tok2.kind == .name {
 		node = p.call_expr(is_c, is_js, mod)
 	} else {
@@ -1105,8 +1105,9 @@ fn (mut p Parser) parse_number_literal() ast.Expr {
 fn (mut p Parser) module_decl() ast.Module {
 	mut name := 'main'
 	is_skipped := p.tok.kind != .key_module
+	mut module_pos := token.Position{}
 	if !is_skipped {
-		module_pos := p.tok.position()
+		module_pos = p.tok.position()
 		p.next()
 		mut pos := p.tok.position()
 		name = p.check_name()
@@ -1121,6 +1122,7 @@ fn (mut p Parser) module_decl() ast.Module {
 				p.error_with_pos('`module x` can only declare one module', pos)
 			}
 		}
+		module_pos = module_pos.extend(pos)
 	}
 	full_mod := p.table.qualify_module(name, p.file_name)
 	p.mod = full_mod
@@ -1128,6 +1130,7 @@ fn (mut p Parser) module_decl() ast.Module {
 	return ast.Module{
 		name: full_mod
 		is_skipped: is_skipped
+		pos: module_pos
 	}
 }
 
@@ -1252,7 +1255,9 @@ fn (mut p Parser) global_decl() ast.GlobalDecl {
 		p.mod != 'ui' && p.mod != 'gg2' && p.mod != 'uiold' && !os.getwd().contains('/volt') && !p.pref.enable_globals {
 		p.error('use `v --enable-globals ...` to enable globals')
 	}
+	start_pos := p.tok.position()
 	p.next()
+	pos := start_pos.extend(p.tok.position())
 	name := p.check_name()
 	// println(name)
 	typ := p.parse_type()
@@ -1280,6 +1285,7 @@ fn (mut p Parser) global_decl() ast.GlobalDecl {
 	glob := ast.GlobalDecl{
 		name: name
 		typ: typ
+		pos: pos
 		has_expr: has_expr
 		expr: expr
 	}
@@ -1296,9 +1302,6 @@ fn (mut p Parser) enum_decl() ast.EnumDecl {
 	p.check(.key_enum)
 	end_pos := p.tok.position()
 	enum_name := p.check_name()
-	if enum_name.len > 0 && !enum_name[0].is_capital() {
-		p.error_with_pos('enum name `$enum_name` must begin with capital letter', end_pos)
-	}
 	name := p.prepend_mod(enum_name)
 	p.check(.lcbr)
 	mut vals := []string{}
@@ -1307,9 +1310,6 @@ fn (mut p Parser) enum_decl() ast.EnumDecl {
 	for p.tok.kind != .eof && p.tok.kind != .rcbr {
 		pos := p.tok.position()
 		val := p.check_name()
-		if !val.is_lower() {
-			p.error_with_pos('field name `$val` must be all lowercase', pos)
-		}
 		vals << val
 		mut expr := ast.Expr{}
 		mut has_expr := false
diff --git a/vlib/v/parser/struct.v b/vlib/v/parser/struct.v
index e0ff2d35cf..8c2dd84417 100644
--- a/vlib/v/parser/struct.v
+++ b/vlib/v/parser/struct.v
@@ -95,8 +95,9 @@ fn (mut p Parser) struct_decl() ast.StructDecl {
 				is_field_mut = true
 				is_field_global = true
 			}
+			field_start_pos := p.tok.position()
 			field_name := p.check_name()
-			field_pos := p.tok.position()
+			field_pos := field_start_pos.extend(p.tok.position())
 			// p.warn('field $field_name')
 			typ := p.parse_type()
 			/*
@@ -288,6 +289,7 @@ fn (mut p Parser) interface_decl() ast.InterfaceDecl {
 	// Parse methods
 	mut methods := []ast.FnDecl{}
 	for p.tok.kind != .rcbr && p.tok.kind != .eof {
+		method_start_pos := p.tok.position()
 		line_nr := p.tok.line_nr
 		name := p.check_name()
 		if util.contains_capital(name) {
@@ -307,6 +309,7 @@ fn (mut p Parser) interface_decl() ast.InterfaceDecl {
 			file: p.file_name
 			return_type: table.void_type
 			is_pub: true
+			pos: method_start_pos.extend(p.prev_tok.position())
 		}
 		if p.tok.kind.is_start_of_type() && p.tok.line_nr == line_nr {
 			method.return_type = p.parse_type()
diff --git a/vlib/v/tests/fn_test.v b/vlib/v/tests/fn_test.v
index d1312e5a2f..9fc65f0181 100644
--- a/vlib/v/tests/fn_test.v
+++ b/vlib/v/tests/fn_test.v
@@ -1,15 +1,11 @@
-// 1 line comment
-
-/* 1 line comment */
-
+// 1 line comment // 1 line comment
 /*
 multi line comment (1)
 multi line comment (2)
 multi line comment (3)
 */
-
 /*
-	multi line comment (1)
+multi line comment (1)
 	/*
 		nested comment
 	*/
@@ -20,44 +16,43 @@ multi line comment (3)
 	/* /* nested comment */ */
 	multi line comment (2)
 */
+type MyFn1 = fn (int) string
 
-type myfn fn (int) string
+type MyFn2 = fn (a int, b int) int
 
-type myfn2 fn (a int, b int) int
-
-type myfn3 fn (int, int)
+type MyFn3 = fn (int, int)
 
 fn myfn4(string)
 
 fn foobar()
 
-fn slopediv(num u32, den u32) int
+fn slopediv(num, den u32) int
 
-type f1 fn ()
+type F1 = fn ()
 
-type f2 fn (voidptr)
+type F2 = fn (voidptr)
 
-type f3 fn (voidptr, voidptr)
+type F3 = fn (voidptr, voidptr)
 
-type f4 fn (voidptr) int
+type F4 = fn (voidptr) int
 
-type f5 fn (int, int) int
+type F5 = fn (int, int) int
 
-type f6 fn (int, int)
+type F6 = fn (int, int)
 
 fn C.atoi(byteptr) int
 
 fn foo() {
 }
 
-type actionf_v fn ()
+type ActionfV = fn ()
 
-type actionf_p1 fn (voidptr)
+type ActionfP1 = fn (voidptr)
 
-type actionf_p2 fn (voidptr, voidptr)
+type ActionfP2 = fn (voidptr, voidptr)
 
 // TODO
-fn modify_array(a mut []int) {
+fn modify_array(mut a []int) {
 	a[0] = 10
 	for i in 0 .. a.len {
 		a[i] = a[i] * 2
@@ -86,7 +81,7 @@ fn test_mut_array() {
 	println(nums.clone())
 }
 
-fn mod_struct(user mut User) {
+fn mod_struct(mut user User) {
 	user.age++
 }
 
@@ -101,7 +96,7 @@ fn test_mut_struct() {
 	assert user.age == 19
 }
 
-fn mod_ptr(buf mut byteptr) {
+fn mod_ptr(mut buf byteptr) {
 	buf[0] = 77
 }
 
@@ -111,7 +106,6 @@ fn test_mut_ptr() {
 	assert buf[0] == 77
 }
 
-
 fn assert_in_bool_fn(v int) bool {
 	assert v < 3
 	return true
@@ -121,7 +115,8 @@ fn test_assert_in_bool_fn() {
 	assert_in_bool_fn(2)
 }
 
-type MyFn fn (int) int
+type MyFn = fn (int) int
+
 fn test(n int) int {
 	return n + 1000
 }
@@ -129,18 +124,21 @@ fn test(n int) int {
 struct MySt {
 	f MyFn
 }
+
 fn test_fn_type_call() {
-    mut arr := []MyFn{}
-    arr << MyFn(test)
+	mut arr := []MyFn{}
+	arr << MyFn(test)
 	// TODO: `arr[0](10)`
 	// assert arr[0](10) == 1010
 	x1 := arr[0]
 	x2 := x1(10)
 	assert x2 == 1010
-
-    st := MySt{f:test}
-    assert st.f(10) == 1010
-
-	st1 := &MySt{f:test}
-    assert st1.f(10) == 1010
+	st := MySt{
+		f: test
+	}
+	assert st.f(10) == 1010
+	st1 := &MySt{
+		f: test
+	}
+	assert st1.f(10) == 1010
 }