Difference between revisions of "C programming/Caveats"

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m (Created page with "This article contains C programming syntaxes and equations that behave in a strange way. =Logical && and logical ||= When using the logical AND (&&) or the logical OR (||) the ex...")
 
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The statement of the left side of && evaluates to ''false'' the rigth side of the statement is never evaluated - and j is never incremented.
 
The statement of the left side of && evaluates to ''false'' the rigth side of the statement is never evaluated - and j is never incremented.
 
=Links=
 
=Links=
*[http://www.eetimes.com/electronics-blogs/other/4394720/Sequence-points-?Ecosystem=embedded&cid=Newsletter+-+Whats+New+on+Embedded.com]
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*[http://www.eetimes.com/electronics-blogs/other/4394720/Sequence-points-?Ecosystem=embedded&cid=Newsletter+-+Whats+New+on+Embedded.com C Sequence points]

Revision as of 07:39, 28 August 2012

This article contains C programming syntaxes and equations that behave in a strange way.

Logical && and logical ||

When using the logical AND (&&) or the logical OR (||) the expression is evaluated from left to right. Consider the following code.

    i=1;
    j=8;
 if (( i == 0 ) && (( j++ ) > 0 )) {
  ...code...
 }

The statement of the left side of && evaluates to false the rigth side of the statement is never evaluated - and j is never incremented.

Links