The GAP manual says that Unbind() can be used to unbind fields of a record
and array elements. I noticed that it also works in the following:
x:=3;
Unbind(x);
x;
<returns appropriate notice that x is unbound>

Is this usage supported?
I find it useful in removing extraneous temporary global variables after
their use, to avoid accidental collisions with variables of the same name
later. - Gene Cooperman