I believe that your 'utf8' case is mostly benchmarking the pulling out of the character count cached in the magic, thus completely missing the original problem.

I was mostly concerned with pointing out that it's important to consider exactly what you're benchmarking.

I'm also not convinced that there is enough of a description of "the original problem" to say whether I missed or not. I'm finding it quite hard to think of an application where the time taken to obtain the length of a string would be very significant?

Except maybe when sorting strings by length, at which point the caching would pretty much negate the first-time cost.

I don't see how your benchmark provides any justification for not using eq ''

Um...cos I modified the original benchmark and didn't think about it. Having just swapped the 'ne's for 'eq's, it does make a suprising difference. Though I haven't thought through whether that's down the efficiency of the operator or the change to the boolean logic.

It did surprise me greatly that ord worked out much faster than bytes::length.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
"I'd rather go naked than blow up my ass"

In reply to Re^5: Alternative to bytes::length() (7% solution) by BrowserUk
in thread Alternative to bytes::length() by creamygoodness

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