Are PHP short tags acceptable to use?

There must be a clear distinction between the PHP short tag (<?) and shorthand echo tag (<?=)

The former is prohibited by the PHP Coding standard, mostly out of common sense because it's a PITA if you ever have to move your code to a server where it's not supported (and you can't enable it). As you say, lots of shared hosts do support shorttags but "lots" isn't all of them. If you want to share your scripts, it's best to use the full syntax.

Whereas the shorthand echo tag <?= cannot be disabled and therefore is fully acceptable to use.

I agree that <? is easier on programmers than <?php but it is possible to do a bulk find-and-replace as long as you use the same form each time.

I don't buy readability as a reason at all. Most serious developers have the option of syntax highlighting available to them.

As ThiefMaster mentions in the comments, as of PHP 5.4, <?= ... ?> tags are supported everywhere, regardless of shorttags settings. This should mean they're safe to use in portable code but that does mean there's then a dependency on PHP 5.4+. If you want to support pre-5.4 and can't guarantee shorttags, you'll still need to use <?php echo ... ?>.

Also, you need to know that ASP tags <% , %> , <%= , and script tag are removed from PHP 7. So if you would like to support long-term portable code and would like switching to the most modern tools consider changing that parts of code.

I'm too fond of <?=$whatever?> to let it go. Never had a problem with it. I'll wait until it bites me in the ass. In all seriousness, 85% of (my) clients have access to php.ini in the rare occasion they are turned off. The other 15% use mainstream hosting providers, and virtually all of them have them enabled. I love 'em.

The problem with this whole discussion lies in the use of PHP as a templating language. No one is arguing that tags should be used in application source files.

However PHP's embeddable syntax allows it to be used as a powerful template language, and templates should be as simple and readable as possible. Many have found it easier to use a much slower, add-on templating engine like Smarty, but for those purists among us who demand fast rendering and a pure code base, PHP is the only way to write templates.

The ONLY valid argument AGAINST the use of short tags is that they aren't supported on all servers. Comments about conflicts with XML documents are ludicrous, because you probably shouldn't be mixing PHP and XML anyway; and if you are, you should be using PHP to output strings of text. Security should never be an issue, because if you're putting sensitive information like database access credentials inside of template files, well then, you've got bigger issues!

Now then, as to the issue of server support, admittedly one has to be aware of their target platform. If shared hosting is a likely target, then short tags should be avoided. But for many professional developers (such as myself), the client acknowledges (and indeed, depends on the fact) that we will be dictating the server requirements. Often I'm responsible for setting up the server myself.

And we NEVER work with a hosting provider that does not give us absolute control of the server configuration -- in such a case we could count on running to much more trouble than just losing short tag support. It just doesn't happen.

So yes -- I agree that the use of short tags should be carefully weighed. But I also firmly believe that it should ALWAYS be an option, and that a developer who is aware of his environment should feel free to use them.

Short tags are coming back thanks to Zend Framework pushing the "PHP as a template language" in their default MVC configuration. I don't see what the debate is about, most of the software you will produce during your lifetime will operate on a server you or your company will control. As long as you keep yourself consistent, there shouldn't be any problems.

UPDATE

After doing quite a bit of work with Magento, which uses long form. As a result, I've switched to the long form of:

<?php and <?php echo

over

<? and <?=

Seems like a small amount of work to assure interoperability.

Because the confusion it can generate with XML declarations. Many people agree with you, though.

An additional concern is the pain it'd generate to code everything with short tags only to find out at the end that the final hosting server has them turned off...

• Short tags are not turned on by default in some webservers (shared hosts, etc.), so code portability becomes an issue if you need to move to one of these.

• Readability may be an issue for some. Many developers may find that <?php catches the eye as a more obvious marker of the beginning of a code block than <? when you scan a file, particularly if you're stuck with a code base with HTML and PHP tightly inter-woven.

As of 2019 I disagree with certain answers here. Recommended to use:

1. Long tags

<?php /* code goes here */ ?>

2. Short echo tags

<?= /* code goes here */ ?>

Reason: They are recommended by the PSR-1 basic coding standard

Other short tags like <? /* code goes here */ ?> are not recommended.

The spec says:

PHP code MUST use the long tags or the short-echo tags; it MUST NOT use the other tag variations.

One situation that is a little different is when developing a CodeIgniter application. CodeIgniter seems to use the shorttags whenever PHP is being used in a template/view, otherwise with models and controllers it always uses the long tags. It's not a hard and fast rule in the framework, but for the most part the framework and a lot of the source from other uses follows this convention.

My two cents? If you never plan on running the code somewhere else, then use them if you want. I'd rather not have to do a massive search and replace when I realize it was a dumb idea.

• Short tags are acceptable to use in cases where you are certain the server will support it and that your developers will understand it.
• Many servers do not support it, and many developers will understand it after seeing it once.
• I use full tags to ensure portability, since it's really not that bad.

With that said, a friend of mine said this, in support of alternate standardized asp-style tags, like <% rather than <?, which is a setting in php.ini called asp_tags. Here is his reasoning:

... arbitrary conventions should be standardized. That is, any time we are faced with a set of possibilities that are all of equal value - such as what weird punctuation our programming language should use to demarcate itself - we should pick one standard way and stick with it. That way we reduce the learning curve of all languages (or whatever the things the convention pertains to).

Sounds good to me, but I don't think any of us can circle the wagons around this cause. In the meantime, I would stick to the full <?php.

Short tag are alwayes available in php. So you do not need echo the first statement in your script

example:

    $a =10;
    <?= $a;//10 
    echo "Hellow";//
    echo "Hellow";

   ?>

Suddenly you need to use for a single php script then u can use it. example:

<html>
<head>
<title></title>
</head>  
<body>
<p>hellow everybody<?= hi;?></p>
<p>hellow everybody  </p> 
<p>hellow everybody  </p>   
</body>
</html>

If you care about XSS then you should use <?= htmlspecialchars(…) ?> most of the time, so a short tag doesn't make a big difference.

Even if you shorten echo htmlspecialchars() to h(), it's still a problem that you have to remember to add it almost every time (and trying to keep track which data is pre-escaped, which is unescaped-but-harmless only makes mistakes more likely).

I use a templating engine that is secure by default and writes <?php tags for me.

3 tags are available in php:

1. long-form tag that <?php ?> no need to directive any configured
2. short_open_tag that <? ?> available if short_open_tag option in php.ini is on
3. shorten tag <?= since php 5.4.0 it is always available

from php 7.0.0 asp and script tag are removed

No, and they're being phased out by PHP 6 so if you appreciate code longevity, simply don't use them or the <% ... %> tags.