diff --git a/vlib/v/ast/ast.v b/vlib/v/ast/ast.v
index aea8fd9cf4..5ba2140eb2 100644
--- a/vlib/v/ast/ast.v
+++ b/vlib/v/ast/ast.v
@@ -8,7 +8,7 @@ import (
 	v.table
 )
 
-pub type TypeDecl = AliasTypeDecl | SumTypeDecl
+pub type TypeDecl = AliasTypeDecl | SumTypeDecl | FnTypeDecl
 
 pub type Expr = InfixExpr | IfExpr | StringLiteral | IntegerLiteral | CharLiteral | 	
 FloatLiteral | Ident | CallExpr | BoolLiteral | StructInit | ArrayInit | SelectorExpr | PostfixExpr | 	
@@ -128,15 +128,17 @@ pub:
 
 pub struct Arg {
 pub:
-	typ  table.Type
-	name string
+	
+	name   string
+	is_mut bool
+	typ    table.Type
 }
 
 pub struct FnDecl {
 pub:
 	name          string
 	stmts         []Stmt
-	typ           table.Type
+	return_type   table.Type
 	args          []Arg
 	is_deprecated bool
 	is_pub        bool
@@ -232,9 +234,9 @@ pub:
 	scope   &Scope
 }
 
-pub struct IdentFunc {
+pub struct IdentFn {
 pub mut:
-	return_type table.Type
+	typ table.Type
 }
 
 pub struct IdentVar {
@@ -244,7 +246,7 @@ pub mut:
 	is_static bool
 }
 
-pub type IdentInfo = IdentFunc | IdentVar
+pub type IdentInfo = IdentFn | IdentVar
 
 pub enum IdentKind {
 	unresolved
@@ -459,6 +461,13 @@ pub:
 	sub_types []table.Type
 }
 
+pub struct FnTypeDecl {
+pub:
+	name    string
+	is_pub  bool
+	typ     table.Type
+}
+
 pub struct DeferStmt {
 pub:
 	stmts []Stmt
diff --git a/vlib/v/ast/str.v b/vlib/v/ast/str.v
index 1f6e3d98ba..7bc9176936 100644
--- a/vlib/v/ast/str.v
+++ b/vlib/v/ast/str.v
@@ -48,10 +48,10 @@ pub fn (node &FnDecl) str(t &table.Table) string {
 		}
 	}
 	f.write(')')
-	if node.typ != table.void_type {
+	if node.return_type != table.void_type {
 		// typ := t.type_to_str(node.typ)
 		// if typ.starts_with('
-		f.write(' ' + t.type_to_str(node.typ))
+		f.write(' ' + t.type_to_str(node.return_type))
 	}
 	return f.str()
 }
diff --git a/vlib/v/checker/checker.v b/vlib/v/checker/checker.v
index e2c6783860..7966fbf6f4 100644
--- a/vlib/v/checker/checker.v
+++ b/vlib/v/checker/checker.v
@@ -204,6 +204,19 @@ pub fn (c mut Checker) call_expr(call_expr mut ast.CallExpr) table.Type {
 			f = f1
 		}
 	}
+	// check for arg (var) of fn type
+	if !found {
+		scope := c.file.scope.innermost(call_expr.pos.pos)
+		if var := scope.find_var(fn_name) {
+			if var.typ != 0 {
+				vts := c.table.get_type_symbol(var.typ)
+				if vts.kind == .function {
+					f = vts.info as table.Fn
+					found = true
+				}
+			}
+		}
+	}
 	if !found {
 		c.error('unknown fn: $fn_name', call_expr.pos)
 	}
@@ -277,11 +290,17 @@ pub fn (c mut Checker) method_call_expr(method_call_expr mut ast.MethodCallExpr)
 		return info.elem_type
 	}
 	if method := c.table.type_find_method(typ_sym, name) {
+		if method_call_expr.args.len < method.args.len-1 {
+			c.error('too few arguments in call to `${typ_sym.name}.$name`', method_call_expr.pos)
+		}
+		else if !method.is_variadic && method_call_expr.args.len > method.args.len+1 {
+			c.error('too many arguments in call to `${typ_sym.name}.$name` ($method_call_expr.args.len instead of $method.args.len)', method_call_expr.pos)
+		}
 		// if name == 'clone' {
 		// println('CLONE nr args=$method.args.len')
 		// }
 		for i, arg_expr in method_call_expr.args {
-			c.expected_type = method.args[i].typ
+			c.expected_type = method.args[i+1].typ
 			c.expr(arg_expr)
 		}
 		method_call_expr.receiver_type = method.args[0].typ
@@ -492,7 +511,7 @@ fn (c mut Checker) stmt(node ast.Stmt) {
 			c.expr(it.expr)
 		}
 		ast.FnDecl {
-			c.fn_return_type = it.typ
+			c.fn_return_type = it.return_type
 			for stmt in it.stmts {
 				c.stmt(stmt)
 			}
@@ -697,8 +716,8 @@ pub fn (c mut Checker) ident(ident mut ast.Ident) table.Type {
 	}
 	// second use, already resovled in unresovled branch
 	else if ident.kind == .function {
-		info := ident.info as ast.IdentFunc
-		return info.return_type
+		info := ident.info as ast.IdentFn
+		return info.typ
 	}
 	// Handle indents with unresolved types during the parsing step
 	// (declared after first usage)
@@ -719,12 +738,13 @@ pub fn (c mut Checker) ident(ident mut ast.Ident) table.Type {
 		}
 		// Function object (not a call), e.g. `onclick(my_click)`
 		if func := c.table.find_fn(name) {
-			ident.name = name
+			fn_type := c.table.find_or_register_fn_type(func)
+			ident.name = name			
 			ident.kind = .function
-			ident.info = ast.IdentFunc{
-				return_type: func.return_type
+			ident.info = ast.IdentFn{
+				typ: fn_type
 			}
-			return func.return_type
+			return fn_type
 		}
 	}
 	// TODO
@@ -889,6 +909,7 @@ pub fn (c mut Checker) enum_val(node ast.EnumVal) table.Type {
 	typ := c.table.get_type_symbol(table.Type(typ_idx))
 	// println('tname=$typ.name')
 	if typ.kind != .enum_ {
+		println('# $typ.kind.str()')
 		c.error('not an enum', node.pos)
 	}
 	// info := typ.info as table.Enum
diff --git a/vlib/v/gen/cgen.v b/vlib/v/gen/cgen.v
index 1dfb4b6b7d..3c7bbaf743 100644
--- a/vlib/v/gen/cgen.v
+++ b/vlib/v/gen/cgen.v
@@ -245,7 +245,7 @@ fn (g mut Gen) stmt(node ast.Stmt) {
 			g.write('return')
 			// multiple returns
 			if it.exprs.len > 1 {
-				styp := g.typ(g.fn_decl.typ)
+				styp := g.typ(g.fn_decl.return_type)
 				g.write(' ($styp){')
 				for i, expr in it.exprs {
 					g.write('.arg$i=')
@@ -375,8 +375,8 @@ fn (g mut Gen) gen_fn_decl(it ast.FnDecl) {
 		if name.starts_with('_op_') {
 			name = op_to_fn_name(name)
 		}
-		// type_name := g.table.type_to_str(it.typ)
-		type_name := g.typ(it.typ)
+		// type_name := g.table.type_to_str(it.return_type)
+		type_name := g.typ(it.return_type)
 		g.write('$type_name ${name}(')
 		g.definitions.write('$type_name ${name}(')
 	}
diff --git a/vlib/v/gen/jsgen.v b/vlib/v/gen/jsgen.v
index 4611a665b8..ec6c904fe0 100644
--- a/vlib/v/gen/jsgen.v
+++ b/vlib/v/gen/jsgen.v
@@ -37,7 +37,7 @@ pub fn (g mut JsGen) writeln(s string) {
 fn (g mut JsGen) stmt(node ast.Stmt) {
 	match node {
 		ast.FnDecl {
-			type_sym := g.table.get_type_symbol(it.typ)
+			type_sym := g.table.get_type_symbol(it.return_type)
 			g.write('/** @return { $type_sym.name } **/\nfunction ${it.name}(')
 			for arg in it.args {
 				arg_type_sym := g.table.get_type_symbol(arg.typ)
diff --git a/vlib/v/parser/fn.v b/vlib/v/parser/fn.v
index 07971e83b4..fe0e2a5e03 100644
--- a/vlib/v/parser/fn.v
+++ b/vlib/v/parser/fn.v
@@ -81,27 +81,18 @@ fn (p mut Parser) fn_decl() ast.FnDecl {
 		is_method = true
 		p.next()
 		rec_name = p.check_name()
-		if p.tok.kind == .key_mut {
-			rec_mut = true
-		}
+		rec_mut = p.tok.kind == .key_mut
+		// if rec_mut {
+		// 	p.check(.key_mut)
+		// }
+		// TODO: talk to alex, should mut be parsed with the type like this?
+		// or should it be a property of the arg, like this ptr/mut becomes indistinguishable
 		rec_type = p.parse_type()
-		args << table.Var{
-			// Receiver is the first arg
-			typ: rec_type
-			name: rec_name
-		}
 		ast_args << ast.Arg{
 			name: rec_name
+			is_mut: rec_mut
 			typ: rec_type
 		}
-		// p.table.register_var(table.Var{
-		// name: rec_name
-		// typ: rec_type
-		// })
-		p.scope.register_var(ast.Var{
-			name: rec_name
-			typ: rec_type
-		})
 		p.check(.rpar)
 	}
 	mut name := ''
@@ -126,6 +117,7 @@ fn (p mut Parser) fn_decl() ast.FnDecl {
 	for ast_arg in ast_args {
 		var := table.Var{
 			name: ast_arg.name
+			is_mut: ast_arg.is_mut
 			typ: ast_arg.typ
 		}
 		args << var
@@ -136,9 +128,9 @@ fn (p mut Parser) fn_decl() ast.FnDecl {
 		// p.table.register_var(var)
 	}
 	// Return type
-	mut typ := table.void_type
+	mut return_type := table.void_type
 	if p.tok.kind.is_start_of_type() {
-		typ = p.parse_type()
+		return_type = p.parse_type()
 	}
 	// Register
 	if is_method {
@@ -147,7 +139,7 @@ fn (p mut Parser) fn_decl() ast.FnDecl {
 		type_sym.register_method(table.Fn{
 			name: name
 			args: args
-			return_type: typ
+			return_type: return_type
 		})
 	}
 	else {
@@ -160,7 +152,7 @@ fn (p mut Parser) fn_decl() ast.FnDecl {
 		p.table.register_fn(table.Fn{
 			name: name
 			args: args
-			return_type: typ
+			return_type: return_type
 			is_variadic: is_variadic
 			is_c: is_c
 		})
@@ -175,7 +167,7 @@ fn (p mut Parser) fn_decl() ast.FnDecl {
 	return ast.FnDecl{
 		name: name
 		stmts: stmts
-		typ: typ
+		return_type: return_type
 		args: ast_args
 		is_deprecated: is_deprecated
 		is_pub: is_pub
@@ -202,6 +194,10 @@ fn (p mut Parser) fn_args() ([]ast.Arg,bool) {
 		mut arg_no := 1
 		for p.tok.kind != .rpar {
 			arg_name := 'arg_$arg_no'
+			is_mut := p.tok.kind == .key_mut
+			if is_mut {
+				p.check(.key_mut)
+			}
 			if p.tok.kind == .ellipsis {
 				p.check(.ellipsis)
 				is_variadic = true
@@ -218,6 +214,7 @@ fn (p mut Parser) fn_args() ([]ast.Arg,bool) {
 			}
 			args << ast.Arg{
 				name: arg_name
+				is_mut: is_mut
 				typ: arg_type
 			}
 		}
@@ -231,7 +228,8 @@ fn (p mut Parser) fn_args() ([]ast.Arg,bool) {
 				p.check(.comma)
 				arg_names << p.check_name()
 			}
-			if p.tok.kind == .key_mut {
+			is_mut := p.tok.kind == .key_mut
+			if is_mut {
 				p.check(.key_mut)
 			}
 			if p.tok.kind == .ellipsis {
@@ -245,6 +243,7 @@ fn (p mut Parser) fn_args() ([]ast.Arg,bool) {
 			for arg_name in arg_names {
 				args << ast.Arg{
 					name: arg_name
+					is_mut: is_mut
 					typ: typ
 				}
 				// if typ.typ.kind == .variadic && p.tok.kind == .comma {
diff --git a/vlib/v/parser/parse_type.v b/vlib/v/parser/parse_type.v
index 29c4ffddbf..d432f04649 100644
--- a/vlib/v/parser/parse_type.v
+++ b/vlib/v/parser/parse_type.v
@@ -66,15 +66,32 @@ pub fn (p mut Parser) parse_multi_return_type() table.Type {
 	return table.new_type(idx)
 }
 
-pub fn (p mut Parser) parse_fn_type() table.Type {
-	// p.warn('parrse fn')
+// given anon name based off signature when `name` is blank
+pub fn (p mut Parser) parse_fn_type(name string) table.Type {
+	// p.warn('parse fn')
 	p.check(.key_fn)
-	// p.fn_decl()
-	p.fn_args()
-	if p.tok.kind.is_start_of_type() {
-		p.parse_type()
+	ast_args, is_variadic := p.fn_args()
+	mut args := []table.Var
+	for ast_arg in ast_args {
+		arg := table.Var{
+			name: ast_arg.name
+			is_mut: ast_arg.is_mut
+			typ: ast_arg.typ
+		}
+		args << arg
 	}
-	return table.int_type
+	mut return_type := table.void_type
+	if p.tok.kind.is_start_of_type() {
+		return_type = p.parse_type()
+	}
+	func := table.Fn{
+		name: name
+		args: args
+		is_variadic: is_variadic
+		return_type: return_type
+	}
+	idx := p.table.find_or_register_fn_type(func)
+	return table.new_type(idx)
 }
 
 pub fn (p mut Parser) parse_type() table.Type {
@@ -137,7 +154,7 @@ pub fn (p mut Parser) parse_any_type(is_c, is_ptr bool) table.Type {
 	match p.tok.kind {
 		// func
 		.key_fn {
-			return p.parse_fn_type()
+			return p.parse_fn_type('')
 		}
 		// array
 		.lsbr {
diff --git a/vlib/v/parser/parser.v b/vlib/v/parser/parser.v
index 371cb8d73d..7d46f140d4 100644
--- a/vlib/v/parser/parser.v
+++ b/vlib/v/parser/parser.v
@@ -1727,6 +1727,16 @@ fn (p mut Parser) type_decl() ast.TypeDecl {
 			sub_types: sum_variants
 		}
 	}
+	// function type: `type mycallback fn(string, int)`
+	if p.tok.kind == .key_fn {
+		fn_name := p.prepend_mod(name)
+		fn_type := p.parse_fn_type(fn_name)
+		return ast.FnTypeDecl{
+			name: fn_name
+			is_pub: is_pub
+			typ: fn_type
+		}
+	}
 	// type MyType int
 	parent_type := p.parse_type()
 	pid := table.type_idx(parent_type)
diff --git a/vlib/v/table/atype_symbols.v b/vlib/v/table/atype_symbols.v
index 71c6024e6a..46d617c00d 100644
--- a/vlib/v/table/atype_symbols.v
+++ b/vlib/v/table/atype_symbols.v
@@ -8,7 +8,7 @@ import (
 )
 
 pub type TypeInfo = Array | ArrayFixed | Map | Struct |
-MultiReturn | Alias | Enum | SumType
+MultiReturn | Alias | Enum | SumType | Fn
 
 pub struct TypeSymbol {
 pub:
@@ -87,6 +87,7 @@ pub enum Kind {
 	sum_type
 	alias
 	enum_
+	function
 }
 
 pub fn (t &TypeSymbol) str() string {
diff --git a/vlib/v/table/table.v b/vlib/v/table/table.v
index fbe355c1f9..35b04b4bd4 100644
--- a/vlib/v/table/table.v
+++ b/vlib/v/table/table.v
@@ -60,6 +60,25 @@ pub fn (t mut Table) register_global(name string, typ Type) {
 	}
 }
 
+// used to compare fn's & for naming anon fn's
+pub fn (f &Fn) signature() string {
+	mut sig := ''
+	for i, arg in f.args {
+		// TODO: for now ignore mut/pts in sig for now
+		typ := type_set_nr_muls(arg.typ, 0)
+		// if arg.is_mut {
+		// 	sig += 'mut_'
+		// }
+		// sig += '$arg.typ'
+		sig += '$typ'
+		if i < f.args.len-1 {
+			sig += '_'
+		}
+	}
+	sig += '_$f.return_type'
+	return sig
+}
+
 pub fn (t &Table) find_fn(name string) ?Fn {
 	f := t.fns[name]
 	if f.name.str != 0 {
@@ -360,6 +379,20 @@ pub fn (t mut Table) find_or_register_multi_return(mr_typs []Type) int {
 	return t.register_type_symbol(mr_type)
 }
 
+pub fn (t mut Table) find_or_register_fn_type(f Fn) int {
+	name := if f.name.len > 0 {
+		f.name
+	}
+	else {
+		'anon_$f.signature()'
+	}
+	return t.register_type_symbol(TypeSymbol{
+		kind: .function
+		name: name
+		info: f
+	})
+}
+
 pub fn (t mut Table) add_placeholder_type(name string) int {
 	ph_type := TypeSymbol{
 		kind: .placeholder
@@ -440,12 +473,20 @@ pub fn (t &Table) check(got, expected Type) bool {
 			return true
 		}
 	}
-	else if exp_type_sym.kind == .sum_type {
+	if exp_type_sym.kind == .sum_type {
 		sum_info := exp_type_sym.info as SumType
 		if got in sum_info.variants {
 			return true
 		}
 	}
+	// fn type
+	if got_type_sym.kind == .function && exp_type_sym.kind == .function {
+		got_fn := got_type_sym.info as Fn
+		exp_fn := exp_type_sym.info as Fn
+		if got_fn.signature() == exp_fn.signature() {
+			return true
+		}
+	}
 	if got_idx != exp_idx {
 		// && got.typ.name != expected.typ.name*/
 		return false