c_gtk_source_gutter_renderer_query_tooltip

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)
int function(GtkSourceGutterRenderer* renderer, GtkTextIter* iter, GdkRectangle* area, int x, int y, GtkTooltip* tooltip) c_gtk_source_gutter_renderer_query_tooltip;

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