The complete expression is evaluated inside-to-outside. The innermost expression is [$i, $i++]. The comma operator, within a list context (which the [] provides), evaluates from right-to-left. (This is different from a scalar context where it evaluates the LHS, discards the value, then evaluates the RHS.)
It's not clearly spelled out, but you can look at p.108 (for the comma operator) and p.109 (for list contexts in general) of the 3rd ed. Camel.
Update: Roy Johnson's answer is much better than mine.
Being right, does not endow the right to be rude; politeness costs nothing.
Being unknowing, is not the same as being stupid.
Expressing a contrary opinion, whether to the individual or the group, is more often a sign of deeper thought than of cantankerous belligerence.
Do not mistake your goals as the only goals; your opinion as the only opinion; your confidence as correctness. Saying you know better is not the same as explaining you know better.
In reply to Re^2: Array slice out of order
by dragonchild
in thread Array slice out of order
by smark
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