diff --git a/cmd/tools/vdoc/html.v b/cmd/tools/vdoc/html.v
index 4a2e8f4133..efba062bb4 100644
--- a/cmd/tools/vdoc/html.v
+++ b/cmd/tools/vdoc/html.v
@@ -326,7 +326,8 @@ fn html_highlight(code string, tb &ast.Table) string {
 						tok_typ = .builtin
 					} else if next_tok.kind == .lcbr {
 						tok_typ = .symbol
-					} else if next_tok.kind == .lpar {
+					} else if next_tok.kind == .lpar
+						|| (!tok.lit[0].is_capital() && next_tok.kind == .lt) {
 						tok_typ = .function
 					} else {
 						tok_typ = .name
diff --git a/cmd/tools/vdoc/utils.v b/cmd/tools/vdoc/utils.v
index 63f5aa0325..08f800abd6 100644
--- a/cmd/tools/vdoc/utils.v
+++ b/cmd/tools/vdoc/utils.v
@@ -206,7 +206,7 @@ fn color_highlight(code string, tb &ast.Table) string {
 					} else if
 						next_tok.kind in [.lcbr, .rpar, .eof, .comma, .pipe, .name, .rcbr, .assign, .key_pub, .key_mut, .pipe, .comma]
 						&& prev.kind in [.name, .amp, .rsbr, .key_type, .assign, .dot, .question, .rpar, .key_struct, .key_enum, .pipe, .key_interface]
-						&& (tok.lit[0].ascii_str().is_upper() || prev_prev.lit in ['C', 'JS']) {
+						&& (tok.lit[0].is_capital() || prev_prev.lit in ['C', 'JS']) {
 						tok_typ = .symbol
 					} else if next_tok.kind in [.lpar, .lt] {
 						tok_typ = .function
@@ -214,7 +214,7 @@ fn color_highlight(code string, tb &ast.Table) string {
 						if tok.lit in ['C', 'JS'] {
 							tok_typ = .prefix
 						} else {
-							if tok.lit[0].ascii_str().is_upper() {
+							if tok.lit[0].is_capital() {
 								tok_typ = .symbol
 							} else {
 								tok_typ = .module_
diff --git a/vlib/builtin/int.v b/vlib/builtin/int.v
index efd93a47ad..236448bcd1 100644
--- a/vlib/builtin/int.v
+++ b/vlib/builtin/int.v
@@ -449,6 +449,7 @@ pub fn (nn u64) hex_full() string {
 }
 
 // str returns the contents of `byte` as a zero terminated `string`.
+// See also: [`byte.ascii_str`](#byte.ascii_str)
 // Example: assert byte(111).str() == '111'
 pub fn (b byte) str() string {
 	return int(b).str_l(7)
diff --git a/vlib/builtin/string.v b/vlib/builtin/string.v
index 70bbd013dc..c1a8f81ab2 100644
--- a/vlib/builtin/string.v
+++ b/vlib/builtin/string.v
@@ -1208,6 +1208,7 @@ pub fn (s string) to_upper() string {
 }
 
 // is_upper returns `true` if all characters in the string is uppercase.
+// See also: [`byte.is_capital`](#byte.is_capital)
 // Example: assert 'HELLO V'.is_upper() == true
 [direct_array_access]
 pub fn (s string) is_upper() bool {