GtkBuildableIface.customTagStart

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
struct GtkBuildableIface
extern (C)
int function(GtkBuildable* buildable, GtkBuilder* builder, GObject* child, char* tagname, GMarkupParser* parser, void** data) customTagStart;

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