Determines the first item type of a tuple or dictionary entry type.
This function may only be used with tuple or dictionary entry types, but must not be used with the generic tuple type G_VARIANT_TYPE_TUPLE.
In the case of a dictionary entry type, this returns the type of the key.
NULL is returned in case of type being G_VARIANT_TYPE_UNIT.
This call, together with Variant.typeNext provides an iterator interface over tuple and dictionary entry types.
the first item type of type, or NULL
Since 2.24
Determines the first item type of a tuple or dictionary entry type.
This function may only be used with tuple or dictionary entry types, but must not be used with the generic tuple type G_VARIANT_TYPE_TUPLE.
In the case of a dictionary entry type, this returns the type of the key.
NULL is returned in case of type being G_VARIANT_TYPE_UNIT.
This call, together with Variant.typeNext provides an iterator interface over tuple and dictionary entry types.