parser: deprecate inline sum types

CHANGELOG.md

@@ -10,8 +10,9 @@
 - DOOM is now translated/compiled and launched on CI servers. A screenshot of the running game
   is made via `vgret` and is compared to the expected result.
 - VLS performance improvements, especially on Windows.
-- Add `v ls` tool for installing, for updating, and for launching VLS (V Language Server)
+- `v ls` tool for installing, for updating, and for launching VLS (V Language Server).
 - Support `assert condition, extra_message`, where the `extra_message` will be evaluated and shown if the assertion fails.
+- Anonymous sumtypes have been removed (deprecated for now) due to complicating the language and the compiler too much.
 
 ## V 0.3
 *30 Jun 2022*

vlib/v/gen/native/gen.v

@@ -124,7 +124,9 @@ struct VarConfig {
 
 type Var = GlobalVar | LocalVar | ast.Ident
 
-fn (mut g Gen) get_var_from_ident(ident ast.Ident) LocalVar|GlobalVar|Register {
+type IdentVar = GlobalVar | LocalVar | Register
+
+fn (mut g Gen) get_var_from_ident(ident ast.Ident) IdentVar {
 	mut obj := ident.obj
 	if obj !in [ast.Var, ast.ConstField, ast.GlobalField, ast.AsmRegister] {
 		obj = ident.scope.find(ident.name) or { g.n_error('unknown variable $ident.name') }

vlib/v/parser/parse_type.v

@@ -305,6 +305,8 @@ pub fn (mut p Parser) parse_language() ast.Language {
 // parse_inline_sum_type parses the type and registers it in case the type is an anonymous sum type.
 // It also takes care of inline sum types where parse_type only parses a standalone type.
 pub fn (mut p Parser) parse_inline_sum_type() ast.Type {
+	p.warn('inline sum types have been deprecated and will be removed on January 1, 2023 due ' +
+		'to complicating the language and the compiler too much; define named sum types with `type Foo = Bar | Baz` instead')
 	variants := p.parse_sum_type_variants()
 	if variants.len > 1 {
 		if variants.len > parser.maximum_inline_sum_type_variants {

vlib/v/parser/tests/anon_sum_type_interface.out

@@ -0,0 +1,5 @@
+vlib/v/parser/tests/anon_sum_type_interface.vv:2:6: warning: inline sum types have been deprecated and will be removed on January 1, 2023 due to complicating the language and the compiler too much; define named sum types with `type Foo = Bar | Baz` instead
+    1 | interface Foo {
+    2 |     bar string | int
+      |         ~~~~~~
+    3 | }

vlib/v/parser/tests/anon_sum_type_struct.out

@@ -0,0 +1,5 @@
+vlib/v/parser/tests/anon_sum_type_struct.vv:2:6: warning: inline sum types have been deprecated and will be removed on January 1, 2023 due to complicating the language and the compiler too much; define named sum types with `type Foo = Bar | Baz` instead
+    1 | struct Foo {
+    2 |     bar string | int
+      |         ~~~~~~
+    3 | }

vlib/v/parser/tests/inline_sum_type_optional_err.out

@@ -1,3 +1,8 @@
+vlib/v/parser/tests/inline_sum_type_optional_err.vv:1:11: warning: inline sum types have been deprecated and will be removed on January 1, 2023 due to complicating the language and the compiler too much; define named sum types with `type Foo = Bar | Baz` instead
+    1 | fn foo() ?string | int {
+      |           ~~~~~~
+    2 |     return 0
+    3 | }
 vlib/v/parser/tests/inline_sum_type_optional_err.vv:1:10: error: an inline sum type cannot be optional
     1 | fn foo() ?string | int {
       |          ~~~~~~~~~~~~~

vlib/v/parser/tests/inline_sum_type_return_type_too_many_variants.out

@@ -1,20 +1,41 @@
+vlib/v/parser/tests/inline_sum_type_return_type_too_many_variants.vv:4:6: warning: inline sum types have been deprecated and will be removed on January 1, 2023 due to complicating the language and the compiler too much; define named sum types with `type Foo = Bar | Baz` instead
+    2 | 
+    3 | struct Foo {
+    4 |     bar int | string | token.Pos | bool | u32
+      |         ~~~
+    5 | }
+    6 |
 vlib/v/parser/tests/inline_sum_type_return_type_too_many_variants.vv:4:6: warning: an inline sum type expects a maximum of 3 types (5 were given)
-    2 |
+    2 | 
     3 | struct Foo {
     4 |     bar int | string | token.Pos | bool | u32
       |         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     5 | }
     6 |
+vlib/v/parser/tests/inline_sum_type_return_type_too_many_variants.vv:7:12: warning: inline sum types have been deprecated and will be removed on January 1, 2023 due to complicating the language and the compiler too much; define named sum types with `type Foo = Bar | Baz` instead
+    5 | }
+    6 | 
+    7 | fn foo(arg int | string | token.Pos | bool | u32) int | string | token.Pos | bool | u32 {
+      |            ~~~
+    8 |     return 1
+    9 | }
 vlib/v/parser/tests/inline_sum_type_return_type_too_many_variants.vv:7:12: warning: an inline sum type expects a maximum of 3 types (5 were given)
     5 | }
-    6 |
+    6 | 
     7 | fn foo(arg int | string | token.Pos | bool | u32) int | string | token.Pos | bool | u32 {
       |            ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     8 |     return 1
     9 | }
+vlib/v/parser/tests/inline_sum_type_return_type_too_many_variants.vv:7:51: warning: inline sum types have been deprecated and will be removed on January 1, 2023 due to complicating the language and the compiler too much; define named sum types with `type Foo = Bar | Baz` instead
+    5 | }
+    6 | 
+    7 | fn foo(arg int | string | token.Pos | bool | u32) int | string | token.Pos | bool | u32 {
+      |                                                   ~~~
+    8 |     return 1
+    9 | }
 vlib/v/parser/tests/inline_sum_type_return_type_too_many_variants.vv:7:51: warning: an inline sum type expects a maximum of 3 types (5 were given)
     5 | }
-    6 |
+    6 | 
     7 | fn foo(arg int | string | token.Pos | bool | u32) int | string | token.Pos | bool | u32 {
       |                                                   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     8 |     return 1

vlib/v/parser/tests/option_sum_type_return_err.out

@@ -1,3 +1,8 @@
+vlib/v/parser/tests/option_sum_type_return_err.vv:1:22: warning: inline sum types have been deprecated and will be removed on January 1, 2023 due to complicating the language and the compiler too much; define named sum types with `type Foo = Bar | Baz` instead
+    1 | fn option_sumtype() ?string | int {
+      |                      ~~~~~~
+    2 |     return 0
+    3 | }
 vlib/v/parser/tests/option_sum_type_return_err.vv:1:21: error: an inline sum type cannot be optional
     1 | fn option_sumtype() ?string | int {
       |                     ~~~~~~~~~~~~~