Should an NSString property under ARC be strong or copy?

objective-c cocoa-touch automatic-ref-counting declared-property
rustylepord picture rustylepord · Jun 28, 2012 · Viewed 23.5k times · Source

When not compiling with ARC, it is recommended to use copy properties for data types such as NSString. I could not find proper documentation on the use of copy in ARC mode. Can someone tell me what's applicable for ARC?

Answer

Joe picture Joe · Jun 28, 2012

It is still recommended to copy because you want to avoid something passing a mutable string and then changing it without you knowing. A copy guarantees that the string you have will not change.

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