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Date: Tue, 17 Jun 2008 07:35:05 -0400
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Subject: Re: [PHP-DEV] deprecation status of $str{42} versus $str[42]
From: edwardzyang@thewritingpot.com ("Edward Z. Yang")

Stefan Walk wrote:
> You're not learning from the mistakes of other languages (ruby in this case, 
> which removed Enumerable from String in 1.9) ... "foreach" makes no sense for 
> strings, because it's unclear what you want (with unicode terminology here, 
> as this is for php6): 
> "for each byte" "for each codeunit" "for each codepoint", or "for each line", 
> or ...

You bring up a good point. However, as a counterpoint, Python does allow
strings to be used as arrays:

s = 'asdf'
for c in s:
    print c

In my opinion, it only makes sense for foreach to emulate the code
snippet I posted above: for binary strings, that means byte-by-byte, and
for Unicode strings, that means codepoint by codepoint.

But as I said, it would be "neat." This is by no means an essential
feature, and I probably wouldn't be able to use it anyway for BC concerns.

> if you want to use foreach in your example, just do 
> foreach (str_split($str) as $value) { ...

I would never do that, because it requires allocating an entire another
PHP array, more than doubling memory usage, just to iterate across a
string. If I'm doing this sort of heavy string processing, I probably
need some semblance of performance.

-- 
 Edward Z. Yang                        GnuPG: 0x869C48DA
 HTML Purifier <http://htmlpurifier.org> Anti-XSS Filter
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