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To: internals@lists.php.net,Rasmus Lerdorf <rasmus@lerdorf.com>
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Date: Fri, 18 Nov 2005 00:06:48 +0100
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Subject: Re: [PHP-DEV] dropping curly braces
From: akorthaus@web.de (Andreas Korthaus)

Hi Rasmus!

Rasmus Lerdorf wrote:
> 
> Very few people converted to using {} so the argument about reading old 
> code doesn't really hold. 

I can't belive that most of the code today is based on <=PHP3 code. I'm 
not talking about such "PHP3 based" code. I'm talking about code, you 
wrote 1 year ago and did not touch for 10 months. Or code you have to 
debug which someone else wrote.

> If you go and grep through all the public 
> code out there, pretty much none of it uses {} for character offsets.

That's the problem - also grep does not know if [] is used for arrays or 
stings. That's the same for programmers, it's often not easy to conclude 
from context - that's my point.

> Having two syntaxes for the same thing makes no sense, and getting rid 
> of [] would break all sorts of stuff.

Do you think it would break more stuff than getting rid of {}? How do 
you know? grep definitely can't help you here.

> The original reason for the {} 
> was a technical one to simplify the parser, but the landscape has 
> changed and that reason no longer exists.

But [] has been marked deprecated in favour of {} for 5 years now. 
Netcraft finds 10 times more php-domains today than 5 years ago.

> As far a code readability and obviousness goes, I doubt anybody would 
> guess their way to the $str{5} syntax.

But you know without understanding of any context, that it's the 6th 
character of the string "$str". When you see $var[5], it could be the 
6th character of a string, or an element of an array... and what about 
the value? You can't be sure that it's a string with length 1, it also 
could be another array, an object, a string with length 4711...

That increases complexity and decreases readability.

> If you were new to PHP and you 
> were going to try to guess how you would get a character offset in a 
> string, what would your first guess be?  Most non-PHP people I have 
> asked have answered []. 

Hm, most people I can think of would seach the manual for a string 
function, and not even think of syntax like {} or []. Some day I found 
{} syntax in the manual, saw that I could use [] too, but which is 
deprecated. {} was a very straightforward syntax in my eyes (at that 
time). If you want to use PHP, you have to know the manual anyway, so I 
don't think this is a big advantage.

> Removing the obvious syntax just doesn't make 
> any sense.  The other place {} is used outside of control blocks is in 
> quoted strings where "{$foo{1}}" is much uglier than "{$foo[1]}".

Yes that's a disadvantage. But one of my most important goals when 
writing scripts (in a major project) is to reduce complexity and make 
scripts as easy to understand as possible. And PHP makes a good job 
here. But I think the {} -> [] change will reduce readability of 
scripts, because both programmers and "grep" can't differ arrays from 
strings using the [] syntax anymore.

However, thanks a lot for your time/explanation!


best regards
Andreas