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How can I check NSAssert of a variable (null)?

the console prints me (null) for a variable that shouldn't be there, so I want to put a statement there just for fun:

NSAssert(myVar, @"myVar was (null)!");

What's the trick here? this (zero) thing doesn't seem to be "nil", right? How can I check this? I want to assume that var is set correctly, not nil, not null.

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3 answers


Assuming it myVar

has a type id

(or any type of object), use

NSAssert(myVar != nil, @"")

If this assertion passed, you should be able to print myVar

to the console with



NSLog(@"myVar = %@", myVar);

As a side note nil==null

(both meanings #defined

like __DARWIN_NULL

that #defined

((void *)0)

). If you try NSLog

to print -description

an object reference nil

(or NULL

), you get "(null)"

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do [myVar isEqualToClass: [NSNull null]] returns yes if it's NSNull if it's nil you can do if (myVar == nil)



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I usually do

if (object != nil)
  doSomething(object);
else
  NSLog("bad object!");
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