c_gtk_source_region_iter_get_subregion

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(GtkSourceRegionIter* iter, GtkTextIter* start, GtkTextIter* end) c_gtk_source_region_iter_get_subregion;

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