parser: do not allow string{} outside of builtin

vlib/compiler/scanner.v

@@ -120,7 +120,7 @@ fn filter_num_sep(txt byteptr, start int, end int) string {
 			i++
 		}
 		b[i1]=0 // C string compatibility
-		return string{str:b len:i1}
+		return string(b, i1)
 	}
 }
 

vlib/v/parser/parser.v

@@ -667,7 +667,7 @@ pub fn (p mut Parser) name_expr() ast.Expr {
 	}
 	else if p.peek_tok.kind == .lcbr && (p.tok.lit[0].is_capital() || is_c ||
 	//
-	p.tok.lit in table.builtin_type_names) &&
+	(p.builtin_mod && p.tok.lit in table.builtin_type_names)) &&
 	//
 	(p.tok.lit.len == 1 || !p.tok.lit[p.tok.lit.len - 1].is_capital())
 	//
@@ -822,7 +822,7 @@ pub fn (p mut Parser) expr(precedence int) ast.Expr {
 					p.error('unknown variable `$name`')
 					return node
 				}
-				println('assoc var $name typ=$var.typ')
+				// println('assoc var $name typ=$var.typ')
 				mut fields := []string
 				mut vals := []ast.Expr
 				p.check(.pipe)

vlib/v/scanner/scanner.v

@@ -124,10 +124,7 @@ fn filter_num_sep(txt byteptr, start int, end int) string {
 			i++
 		}
 		b[i1] = 0 // C string compatibility
-		return string{
-			str: b
-			len: i1
-		}
+		return string(b,i1)
 	}
 }