• Open Menu Close Menu
  • Apple
  • Shopping Bag
  • Apple
  • Mac
  • iPad
  • iPhone
  • Watch
  • TV
  • Music
  • Support
  • Search apple.com
  • Shopping Bag

Lists

Open Menu Close Menu
  • Terms and Conditions
  • Lists hosted on this site
  • Email the Postmaster
  • Tips for posting to public mailing lists
Re: Avoiding == and = mixup in if statements
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Avoiding == and = mixup in if statements


  • Subject: Re: Avoiding == and = mixup in if statements
  • From: Nicko van Someren <email@hidden>
  • Date: Fri, 21 May 2004 04:03:57 +0100

On 21 May 2004, at 3:10, Christoffer Lerno wrote:

Java disallows stuff like

if (myObject=nil) { dosomething }

Is it possible to maybe disallow the same potential error when I'm
writing obj-c programs? Could I do something with the pre-processor
perhaps?

Yes, sort of. You can add -Wparentheses to make the compiler warm you when you write if (a=b)... and you'll get the message "warning: suggest parentheses around assignment used as truth value". If it is really what you meant you can say if ((a=b))... instead. This will also happen if you use the more general flag -Wall. For production code it's often a good plan to include -Werror in the C flags, so that the code will not compile when there are outstanding warnings, but it can become very irritating during initial development phases.

Nicko
_______________________________________________
cocoa-dev mailing list | email@hidden
Help/Unsubscribe/Archives: http://www.lists.apple.com/mailman/listinfo/cocoa-dev
Do not post admin requests to the list. They will be ignored.


  • Follow-Ups:
    • Re: Avoiding == and = mixup in if statements
      • From: Hasan Diwan <email@hidden>
References: 
 >Avoiding == and = mixup in if statements (From: Christoffer Lerno <email@hidden>)

  • Prev by Date: Re: Avoiding == and = mixup in if statements
  • Next by Date: Re: NSMakePoint and such - what about memory allocation?
  • Previous by thread: Re: Avoiding == and = mixup in if statements
  • Next by thread: Re: Avoiding == and = mixup in if statements
  • Index(es):
    • Date
    • Thread