This interface is used to denote that an object is capable of being
a completion proposal for [class@Completion].
Currently, no method or functions are required but additional methods
may be added in the future. Proposals created by
#GtkSourceCompletionProvider can use [func@GObject.IMPLEMENT_INTERFACE] to
implement this with %NULL for the interface init function.
Interface for completion proposals.
This interface is used to denote that an object is capable of being a completion proposal for [class@Completion].
Currently, no method or functions are required but additional methods may be added in the future. Proposals created by #GtkSourceCompletionProvider can use [func@GObject.IMPLEMENT_INTERFACE] to implement this with %NULL for the interface init function.