This has little or nothing to do with order of precedence. It has to do with the fact that when side effects happen is undefined. That means that, regardless of any parenthesization, any expression that uses a variable with autoincrement more than once likely has multiple possible acceptable values.

Consider $i++ + $i
The 2nd $i could be either the incremented value or the unincremented value. Parentheses won't change that, because the increment happens at some undefined time. The value of $i++ is defined as the unincremented value, but if you use $i elsewhere in the same statement, Perl does not guarantee you what its value will be.

Caution: Contents may have been coded under pressure.

In reply to Re^2: Auto Increment "magic" Inquiry by Roy Johnson
in thread Auto Increment "magic" Inquiry by brusimm

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