The order of evaluation is undefined within the C spec, thus it's undefined within the Perl spec.

I understand the reasoning behind this decision in C, but my question really centres upon one word in the sentance I quoted above: "thus". The most salient definition of that word in relation to that sentance is:

Therefore; consequently:

Does it follow that because code could be made more efficient at the C-level by not defining execution order, that the same would be true for Perl? Given that most of not all Perl opcodes are fairly heavy relative to the equivalent C code, I wonder if there is any real scope for improving efficiency at the Perl level by not defining execution order.

Ultimately, I wonder if Perl 6 could define an execution order without penalty? And whether that would be a good thing to do in terms of the usability and teh principil of least surprise?

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
Lingua non convalesco, consenesco et abolesco.
Rule 1 has a caveat! -- Who broke the cabal?

In reply to Re^2: Why is the execution order of subexpressions undefined? by BrowserUk
in thread Why is the execution order of subexpressions undefined? by BrowserUk

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