general / nullp

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NAME

nullp() - determine whether or not a given variable is null.

SYNOPSIS

int nullp( mixed arg );

DESCRIPTION

Return 1 if 'arg' is null.  'arg' will be null in the following cases:

1.     it has not yet been initialized.

2.     it points to a destructed object.

3.     it  is a function (formal) parameter that corresponds to a miss‐
ing actual argument.

SEE ALSO

mapp(3),  stringp(3),  pointerp(3),  objectp(3),  intp(3),  bufferp(3),
floatp(3), functionp(3), undefinedp(3), errorp(3)