Difference between revisions of "C programming/Caveats"
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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. | ||
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i=0; | i=0; | ||
Latest revision as of 15:17, 10 February 2013
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.
or
i=0;
j=8;
if (( i == 0 ) || (( j++ ) > 0 )) {
...code...
}
The statement of the left side of || evaluates to true the rigth side of the statement is never evaluated - and j is never incremented.