Make duck-typing easier

* Use flag struct based on command enum to enable commands
* Include cmds argument as public declaration inside Wrapper structs
* Include Dispatch type as public declaration inside Wrapper structs
This commit is contained in:
InKryption
2021-12-28 12:52:52 +01:00
parent eb4373bb7c
commit fd4302f848
2 changed files with 112 additions and 88 deletions

View File

@@ -1006,31 +1006,51 @@ fn Renderer(comptime WriterType: type) type {
};
try self.writer.print(
\\pub fn {s}Wrapper(comptime cmds: []const {s}Command) type {{
\\ comptime var fields: [cmds.len]std.builtin.TypeInfo.StructField = undefined;
\\ inline for (cmds) |cmd, i| {{
\\ const PfnType = cmd.PfnType();
\\ fields[i] = .{{
\\ .name = cmd.symbol(),
\\ .field_type = PfnType,
\\ .default_value = null,
\\ .is_comptime = false,
\\ .alignment = @alignOf(PfnType),
\\ }};
\\ }}
\\ const Dispatch = @Type(.{{
\\ .Struct = .{{
\\ .layout = .Auto,
\\ .fields = &fields,
\\ .decls = &[_]std.builtin.TypeInfo.Declaration{{}},
\\ .is_tuple = false,
\\ }},
\\ }});
\\pub const {0s}CommandFlags = std.enums.EnumFieldStruct({0s}Command, bool, false);
\\pub fn {0s}Wrapper(comptime cmds: {0s}CommandFlags) type {{
\\ return struct {{
\\ dispatch: Dispatch,
\\
\\ const Self = @This();
, .{ name, name });
\\ pub const commands = cmds;
\\ pub const Dispatch = Dispatch: {{
\\ @setEvalBranchQuota(2000);
\\ const TypeInfo = std.builtin.TypeInfo;
\\ const fields_len = fields_len: {{
\\ var fields_len = 0;
\\ for (std.meta.fieldNames({0s}Command)) |field_name| {{
\\ fields_len += @boolToInt(@field(cmds, field_name));
\\ }}
\\ break :fields_len fields_len;
\\ }};
\\ var fields_array: [fields_len]TypeInfo.StructField = undefined;
\\ var fields: []TypeInfo.StructField = fields_array[0..];
\\ fields.len = 0;
\\
\\ for (std.enums.values({0s}Command)) |cmd_tag| {{
\\ if (@field(cmds, @tagName(cmd_tag))) {{
\\ const PfnType = cmd_tag.PfnType();
\\ fields.len += 1;
\\ fields[fields.len - 1] = TypeInfo.StructField{{
\\ .name = cmd_tag.symbol(),
\\ .field_type = PfnType,
\\ .default_value = null,
\\ .is_comptime = false,
\\ .alignment = @alignOf(PfnType),
\\ }};
\\ }}
\\ }}
\\ break :Dispatch @Type(.{{
\\ .Struct = .{{
\\ .layout = .Auto,
\\ .fields = fields,
\\ .decls = &[_]std.builtin.TypeInfo.Declaration{{}},
\\ .is_tuple = false,
\\ }},
\\ }});
\\ }};
\\
, .{ name });
try self.renderWrapperLoader(dispatch_type);