Generate Mojom Types in Go

mojo/public/tools/bindings/generators/go_templates/struct.tmpl

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 {% import "encoding_macros.tmpl" as encoding_macros %}
+{% import "mojom_type_macros.tmpl" as mojom_type_macros %}
+{% import "mojom_util_macros.tmpl" as util %}
 
-{% macro define(struct, exported=True) %}
+{% macro define(struct, typepkg, package, exported=True) %}
 type {{struct|name(exported)}} struct {
 {% for field in struct.fields %}
         {{field|name(exported)}} {{field.kind|go_type}}
 {% endfor %}
 }
 
 func (s *{{struct|name(exported)}}) Encode(encoder *bindings.Encoder) error {
 {% set HEADER_SIZE = 8 %}
         encoder.StartStruct({{struct.versions[-1].num_bytes - HEADER_SIZE}}, {{struct.versions[-1].version}})
 {% for byte in struct.bytes %}
@@ skipping 38 matching lines @@
                 {{encoding_macros.decode('s.'~packed_field.field|name(exported), packed_field.field.kind)|tab_indent(2)}}
         }
 {%   endfor %}
 {% endfor %}
         if err := decoder.Finish(); err != nil {
                 return err
         }
         return nil
 }
 
+var {{util.structName(struct, typepkg, package)}} = {{

[mattr, 2015/09/17 00:37:35]

What if instead of declaring global exported variables we added functions
sibling to Decode (say MojomType()) that returned the type.

I'm a little worried that having these mutable global type descriptors will be
error prone, and also may be difficult to replicate in languages that don't
allow you to build complex literals at global scope.

Another idea would be to just make unexported functions that build literals
here, and then hang a function of the request object that give you complete
literals for the request and response types (by using these functions).

Do either of those sound workable?

[alexfandrianto, 2015/10/09 17:43:55]

I need some level of globalness and will only expose global strings and
functions. In my latest CL, most of them are unexposed strings and functions,
with only the identifiers and Descriptor() being exposed.

+  mojom_type_macros.writeMojomType(typepkg, struct, package, exported) }}
+
 {% endmacro %}