📄 nullp
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nnnnuuuullllllllpppp((((3333)))) MMMMuuuuddddOOOOSSSS ((((5555 SSSSeeeepppp 1111999999994444)))) nnnnuuuullllllllpppp((((3333)))) NNNNAAAAMMMMEEEE nullp() - determine whether or not a given variable is null. SSSSYYYYNNNNOOOOPPPPSSSSIIIISSSS int nullp( mixed arg ); DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN 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 missing actual argument. SSSSEEEEEEEE AAAALLLLSSSSOOOO mapp(3), stringp(3), pointerp(3), objectp(3), intp(3), bufferp(3), floatp(3), functionp(3), undefinedp(3), errorp(3) Page 1 (printed 3/16/95)
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