What exactly does rangeOfCharacterFromSet do?

Question

  NSString *foo = @"     x   ";
  NSRange r = [foo rangeOfCharacterFromSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
  NSLog(@"foo range = %d,%d",r.location, r.length);

Results in "foo range = 0,1"

So will it ever return a length > 1?

Solution

See the documentation for that method, and for the more general method it's implemented with.

Comments

[Rob Napier]

It may be helpful here to note that the reader should consult rangeOfCharacterFromSet:options:range: to understand the full details and why length can be greater than 1. The linked function implies you need to keep reading (and then keep reading again since the reference method points to to yet another), but may be confusing to those unfamiliar with Apple's doc style.

[farhadf]

Thanks - I had actually read the documentation for the function I was using, and had not continued to read, so I didn't see the "discussion" note in rangeOfCharacterFromSet:options:range:.

[Nico]

@Rob Napier: Thanks again; while updating the link just now, I took the opportunity to add a link to the more specific method (with the actual explanation, as you note) to make it clearer.