Edit report at https://bugs.php.net/bug.php?id=40296&edit=1
ID: 40296 Comment by: kinghfb+php at gmail dot com Reported by: mail at tobyinkster dot co dot uk Summary: "unless" control structure Status: Wont fix Type: Feature/Change Request Package: *General Issues Operating System: All PHP Version: 5.2.0 Block user comment: N Private report: N New Comment: The structure adds sugar without necessarily breaking anything (with the exception of existing unless() functions, as Rasmus mentioned). I really don't think the double-negatives argument works here, as we're already doing that with 'if', meaning that the readability is quite low in some cases. My only concern is that the structure seems to be more easily convoluted than 'if', potentially leading to nightmarish comprehension tasks. Previous Comments: ------------------------------------------------------------------------ [2012-07-29 20:36:46] hi at brennannovak dot com I like this idea quite a bit- of course I am a native english speaker as well (American), but considering this is used in Ruby & Python the language barrier is not too great that it hinders use. Additionally there are *many* abbreviations in PHP that consist of multiple "english" words which developers are able to understand such as strcmp() Once I memorize what a group of characters *do* I stop thinking about the words that make up the function. ------------------------------------------------------------------------ [2012-07-29 20:25:43] email at philsturgeon dot co dot uk Thanks for stopping by Rasmus, that was a really quick follow up. I think you might have pointed out the crux of the confusion: being a native English speaker. To me it makes perfect sense, but I am British. Unless the condition is true, do this. I like the post: https://37signals.com/svn/posts/2699-making-sense-with-rubys- unless A new keyword just to replace "if ( ! (condition))" might seem like a hassle, and the objective of the game is not always to make PHP "nice", but it is readable and logical to many, and is easy to ignore if you don't like it - unless you have function unless(), but the chances are that function is doing something similar anyway. ------------------------------------------------------------------------ [2012-07-29 20:16:53] ras...@php.net Any new keyword breaks BC to some extent because it will break any code that has an existing unless() function. I agree with others here that unless() can be quite confusing. A negated conditional keyword lends itself to double negatives. It also isn't a very common feature in other languages and definitely not obvious to non-native English speaking people like myself. It is an odd word that essentially means not-if even though it logically should be equivalent to "more" as in the opposite of "more" would be "less" and sticking "un" in front of it suddenly completely changes the meaning entirely. ------------------------------------------------------------------------ [2012-07-29 20:00:40] email at philsturgeon dot co dot uk I am surprised to see such a lack of interest on this feature request. Ruby and Perl both have "unless", and while that is certainly not a reason on its own, it does show that this is used. There are two people here saying that unless is confusing. How so? If something matches false then do whatever. It has an else too, so if something is true it will be used. The main point here is not to remove a single !, but to make much cleaner syntax. if ( ! (isset($foo) or ($foo !== 'bar')) exit('invalid value'); or unless (isset($foo) and $foo === 'bar') exit('invalid value'); Its a minor difference as I cannot remember a more compelling example, but there have been numerous times I have wished to reverse this and have unless instead of an extremely complex if statement. Unless just makes sense, it's optional, it doesn't break BC, it makes syntax easier to read in some situations and it is easy to document. If I knew enough C I'd send in a patch right now as PHP would be better off for having this. ------------------------------------------------------------------------ [2011-12-30 13:50:47] joke at nakhon dot net I vote against this request. Both perl and ruby's 'unless' confuse me so much. It can be easy to abuse. I often encounter someone wrote code like this: unless a != 7 b = 3 else b = 6 end ------------------------------------------------------------------------ The remainder of the comments for this report are too long. To view the rest of the comments, please view the bug report online at https://bugs.php.net/bug.php?id=40296 -- Edit this bug report at https://bugs.php.net/bug.php?id=40296&edit=1