As you can see from the listing in perlop, the assignment operator ("=") has right associativity, which means that the right side is evaluated before the left side.

Incidentally, this is the very reason that the following common idiom works as you expect:

$x = $y = 42;

[download]

Had "=" its left side evaluated first, the 42 would not make it into the $y variable, which would lead to code breakage all over the planet ;)

Update: Hm, scratch that, I think I confused a few terms. The associativity tells us how the statement gets parsed, not how it gets executed.

In reply to Re: Will "$_[0]=shift" always resolve shift first? by betterworld
in thread Will "$_[0]=shift" always resolve shift first? by kyle

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