From e3f8d448c18f8b9d0900b06e108d6edab4dc5ca6 Mon Sep 17 00:00:00 2001
From: Alexander Medvednikov <alexander@vlang.io>
Date: Fri, 8 Jan 2021 04:49:13 +0100
Subject: [PATCH] all: [noinit] struct attribute

---
 tutorials/code/blog/blog.v | 10 +++-------
 vlib/v/checker/checker.v   |  7 +++++++
 vlib/v/parser/struct.v     |  1 +
 vlib/v/table/types.v       |  2 ++
 vlib/vweb/vweb.v           |  1 +
 5 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/tutorials/code/blog/blog.v b/tutorials/code/blog/blog.v
index 75fc08cf5f..c17a34de16 100644
--- a/tutorials/code/blog/blog.v
+++ b/tutorials/code/blog/blog.v
@@ -33,11 +33,8 @@ pub fn (app &App) index() vweb.Result {
 
 pub fn (mut app App) init_once() {
 	app.db = sqlite.connect('blog.db') or { panic(err) }
-	app.db.exec('create table if not exists article (' +
-	'id integer primary key, ' + 
-	"title text default ''," +
-	"text text default ''" +
-	');')
+	app.db.exec('create table if not exists article (' + 'id integer primary key, ' + "title text default ''," +
+		"text text default ''" + ');')
 }
 
 pub fn (mut app App) init() {
@@ -53,8 +50,7 @@ pub fn (mut app App) new_article() vweb.Result {
 	title := app.form['title']
 	text := app.form['text']
 	if title == '' || text == '' {
-		app.text('Empty text/title')
-		return vweb.Result{}
+		return app.text('Empty text/title')
 	}
 	article := Article{
 		title: title
diff --git a/vlib/v/checker/checker.v b/vlib/v/checker/checker.v
index fc91ee7626..c7c40acae2 100644
--- a/vlib/v/checker/checker.v
+++ b/vlib/v/checker/checker.v
@@ -504,6 +504,13 @@ pub fn (mut c Checker) struct_init(mut struct_init ast.StructInit) table.Type {
 		type_sym.language != .c {
 		c.error('type `$type_sym.name` is private', struct_init.pos)
 	}
+	if type_sym.kind == .struct_ {
+		info := type_sym.info as table.Struct
+		if info.attrs.len > 0 && info.attrs[0].name == 'noinit' && type_sym.mod != c.mod {
+			c.error('struct `$type_sym.name` is declared with a `[noinit]` attribute, so ' + 'it cannot be initialized with `$type_sym.name{}`',
+				struct_init.pos)
+		}
+	}
 	match type_sym.kind {
 		.placeholder {
 			c.error('unknown struct: $type_sym.name', struct_init.pos)
diff --git a/vlib/v/parser/struct.v b/vlib/v/parser/struct.v
index bc5c6e5098..5341dd0d24 100644
--- a/vlib/v/parser/struct.v
+++ b/vlib/v/parser/struct.v
@@ -295,6 +295,7 @@ fn (mut p Parser) struct_decl() ast.StructDecl {
 			is_union: is_union
 			is_ref_only: attrs.contains('ref_only')
 			generic_types: generic_types
+			attrs: attrs
 		}
 		is_public: is_pub
 	}
diff --git a/vlib/v/table/types.v b/vlib/v/table/types.v
index dc35814ab0..7c0b029451 100644
--- a/vlib/v/table/types.v
+++ b/vlib/v/table/types.v
@@ -603,6 +603,8 @@ pub fn (kinds []Kind) str() string {
 }
 
 pub struct Struct {
+pub:
+	attrs         []Attr
 pub mut:
 	embeds        []Type
 	fields        []Field
diff --git a/vlib/vweb/vweb.v b/vlib/vweb/vweb.v
index 202aacabba..b3737cad35 100644
--- a/vlib/vweb/vweb.v
+++ b/vlib/vweb/vweb.v
@@ -72,6 +72,7 @@ pub struct Cookie {
 	http_only bool
 }
 
+[noinit]
 pub struct Result {
 }