gobject:param-value-validate (pspec value)

pspec -- a valid g:param-spec instance
value -- a g:value instance of correct type for pspec

The boolean whether modifying value was necessary to ensure validity.

Ensures that the contents of value comply with the specifications set out by pspec.

For example, a g:param-spec-int instance might require that integers stored in value may not be smaller than -42 and not be greater than +42. If value contains an integer outside of this range, it is modified accordingly, so the resulting value will fit into the range -42 .. +42.