c_gtk_source_completion_provider_get_start_iter

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)
gboolean function(GtkSourceCompletionProvider* provider, GtkSourceCompletionContext* context, GtkSourceCompletionProposal* proposal, GtkTextIter* iter) c_gtk_source_completion_provider_get_start_iter;

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