c_gtk_builder_extend_with_template

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
__gshared extern (C)
uint function(GtkBuilder* builder, GtkWidget* widget, GType templateType, const(char)* buffer, size_t length, GError** err) c_gtk_builder_extend_with_template;

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