Objective C : constant strings and c strings

Question

In Objective-C, I sometimes forget the @ that defines constant strings. See this example :

NSArray *colors = [NSArray arrayWithObjects:
                      @"Red", @"Green", "Blue", @"Yellow", nil];

In the example, I forgot the @ in front of the "Blue" string. This leads to annoying "Bad Access" bugs.

How to prevent these issues ? Is there some way with XCode to detect these strings or to display warnings ?

Proper testing prevents this from making it to release. Beyond that, you're on your own. — mah
– mah, Commented Jul 8, 2013 at 10:17

Matthias Bauch · Accepted Answer · 2013-07-08 11:08:37Z

4

Run the analyzer, it'll show this:

Argument to 'NSArray' method 'arrayWithObjects:' should be an Objective-C pointer type, not 'char *'

answered Jul 8, 2013 at 11:08

Matthias Bauch

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Comments

David Rönnqvist · Accepted Answer · 2013-07-08 10:14:44Z

3

It seems to me that the literal syntax considers that an error

NSArray *colors = @[@"Red", @"Green", "Blue", @"Yellow"];

Like seen below

enter image description here

answered Jul 8, 2013 at 10:14

David Rönnqvist

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It gives an error because it uses arrayWithObjects:count: which expects const id[] as the first parameter.