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Article:
  Strings in Cocoa: Part I
Subject:   Comparing strings
Date:   2001-07-04 18:36:41
From:   bigboytoddy
Response to: Comparing strings

Okay, so when are each used, and why? I appreciate the ANSI C lessons here, as it seems
it is a ANSI issue, which brings me to ask why (again)? Where would this differentiation make a slack ass like me what to know the difference...?


Thanks


\t

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  • Comparing strings
    2001-07-04 23:33:56  canyonrat [View]

    What this is telling me is that you almost always want char* s rather than char[] s. The first form gives gcc permission to be smart about checking whether you have already used the string and, if you have, just reusing it rather than saving a mew copy and bloating your code.

    For example consider:
    char* aString = "hello";
    and later
    char* bString = "hello"

    the compiler has permission to notice that aString == bString and just reuse aString.

    The second form says that you might want to change bString later and you don't want that to effect aString so they must be stored separately. But you won't need this second form in ObjC because you can use NSMutableString instead.

    Of course the best rule for C style strings is don't use them at all. They are just too complicated and error prone.