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digitalmars.D.bugs - assignment in ? operator

reply "Ilya Zaitseff" <sark7 mail333.com> writes:
[bug.d]

void main()
{
   int a, b, c;
   (a < 0) ? b = 1 : c = 2;
}

Compiler [dmd 0.101] outputs:

bug.d(4): b = 1 is not an lvalue
bug.d(4): #b = 1 is not an lvalue
bug.d(4): #c is not an lvalue
Sep 05 2004
parent reply Stewart Gordon <smjg_1998 yahoo.com> writes:
Ilya Zaitseff wrote:


 [bug.d]
 
 void main()
 {
   int a, b, c;
   (a < 0) ? b = 1 : c = 2;
 }
 
 Compiler [dmd 0.101] outputs:
 
 bug.d(4): b = 1 is not an lvalue
 bug.d(4): #b = 1 is not an lvalue
 bug.d(4): #c is not an lvalue



http://www.digitalmars.com/d/expression.html

	AssignExpression:
		ConditionalExpression
		ConditionalExpression = AssignExpression
		ConditionalExpression += AssignExpression
		ConditionalExpression -= AssignExpression
		ConditionalExpression *= AssignExpression
		ConditionalExpression /= AssignExpression
		ConditionalExpression %= AssignExpression
		ConditionalExpression &= AssignExpression
		ConditionalExpression |= AssignExpression
		ConditionalExpression ^= AssignExpression
		ConditionalExpression ~= AssignExpression
		ConditionalExpression <<= AssignExpression
		ConditionalExpression >>= AssignExpression
		ConditionalExpression >>>= AssignExpression

	ConditionalExpression:
		OrOrExpression
		OrOrExpression ? Expression : ConditionalExpression

So your code means

     ((a < 0) ? b = 1 : c) = 2;

You need to tell it otherwise.

Stewart.

-- 
My e-mail is valid but not my primary mailbox.  Please keep replies on 
the 'group where everyone may benefit.
Sep 06 2004
parent "Ilya Zaitseff" <sark7 mail333.com> writes:
Stewart Gordon wrote:


 Ilya Zaitseff wrote:


 [bug.d]
  void main()
 {
   int a, b, c;
   (a < 0) ? b = 1 : c = 2;
 }
  Compiler [dmd 0.101] outputs:
  bug.d(4): b = 1 is not an lvalue
 bug.d(4): #b = 1 is not an lvalue
 bug.d(4): #c is not an lvalue



 http://www.digitalmars.com/d/expression.html

 	AssignExpression:
 		ConditionalExpression
 		ConditionalExpression = AssignExpression
 		ConditionalExpression += AssignExpression
 		ConditionalExpression -= AssignExpression
 		ConditionalExpression *= AssignExpression
 		ConditionalExpression /= AssignExpression
 		ConditionalExpression %= AssignExpression
 		ConditionalExpression &= AssignExpression
 		ConditionalExpression |= AssignExpression
 		ConditionalExpression ^= AssignExpression
 		ConditionalExpression ~= AssignExpression
 		ConditionalExpression <<= AssignExpression
 		ConditionalExpression >>= AssignExpression
 		ConditionalExpression >>>= AssignExpression

 	ConditionalExpression:
 		OrOrExpression
 		OrOrExpression ? Expression : ConditionalExpression

 So your code means

      ((a < 0) ? b = 1 : c) = 2;

 You need to tell it otherwise.

 Stewart.



You right. Thanks!
Sep 06 2004