PHP: Increment & Decrement


A quick overview of how it works.
POST-INCREMENT ($a++):
Keep in mind with this operator that what comes first gets processed first. (ie: $a++ or ++$a)
For $a++ the rule tells us that we must solve the variables first and then apply the ++ (1+) operator. As a result, the operator does not depend on the variable solving process
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So if: $a=2 $b=$a++
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That means: $a=2 $b=$a ---> $b=2
Then solve the ++ (+1) operation
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$a=2, $a++ = 2+1 ($a+1) ---> $a++=3, $a=3
Answer Post-increase:
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($a++): $a=3 $b=2
PRE-INCREMENT (++$a):
The rule says that the ++ (1+) operator gets processed first and then the rest of the variables.
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So: $a=2 $b=++$a
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That means: $a=2(+1) --> $a=3
After the ++ operation the variables may be solved.
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So: $a=3, $b=a --> $b=3
Because the ++ operator was already solved at the beginning, it does not need to be solved again.
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Answer of Pre-increase: (++$a): $a=3 $b=3
Decrement works in the same fashion.
Last edit: by Mehtuus