libxrdeveloper's documentation
gboolean xr_value_to_value ( xr_value val,
xr_value **  nval 
)

Just a convenience interface to xr_value_ref.

Parameters
valValue node. May be NULL, see below.
nvalPointer to the variable where value should be extracted. This pointer must not be NULL.
Returns
This function returns FALSE if val is NULL, otherwise TRUE is returned.
Documentation for libxr, Wed Apr 27 2016 22:07:49.