GValue is a generic container for arbitrary value of type supported by GType system. Refer to GObject documentation for more detailed information.
CL-GTK2-GOBJECT works with GValue as a foreign type g-value. Functions g-value-zero, g-value-type, g-value-init, parse-g-value, set-g-value are used to inspect and assign GValues. g-value is a CFFI foreign type that is used by all these functions. Pointer to foreign instance of this type is passed to them.
GValue is used whenever a value of unkown type should be passed. It is used in:
Example of usage:
(cffi:with-foreign-object (gval 'g-value)
(set-g-value gval "Hello" "gchararray" :zero-g-value t)
(format t "~S~%" (parse-g-value gval))
(g-value-unset gval))
=>
"Hello"