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Re: Do you use extra parenthesis for include/require/echo?

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Thomas 'PointedEars' Lahn <PointedEars@web.de> writes:

> Ben Bacarisse wrote:
>
>> I don't use the parentheses.  There are some traps to using them that
>> are harder to fall into if you never do.  For example, the expression
>> 
>>   include("x.php") ? "all good" : "failed to include file"
>> 
>> does not parse as if include is a function.
>
> (Your examples are missing a semicolon to be proper PHP code.  Semicolons 
> are not optional in PHP, and there is no ASI.)

I deliberately wrote an expression and not a statement.

> As the “include” statement is part of an expression here, it should parse 
> like a function call.  I consider it a bug that it does not:

It is, however, documented behaviour (which in no way means you should
not consider it a bug).  I just think it's one of several places where
PHP's syntax is a little surprising.

> $ php -r 'include("x.php") ? "all good" : "failed to include file";'
> PHP Warning:  include(all good): failed to open stream: No such file or 
> directory in Command line code on line 1
> PHP Stack trace:
> PHP   1. {main}() Command line code:0
> PHP Warning:  include(): Failed opening 'all good' for inclusion 
> (include_path='.:/usr/share/php:/home/pelinux/LCARS/scripts/php') in Command 
> line code on line 1
> PHP Stack trace:
> PHP   1. {main}() Command line code:0
>
> $ php -v
> PHP 5.6.2-1 (cli) (built: Oct 17 2014 16:36:45) 
> Copyright (c) 1997-2014 The PHP Group
> Zend Engine v2.6.0, Copyright (c) 1998-2014 Zend Technologies
>     with Zend OPcache v7.0.4-dev, Copyright (c) 1999-2014, by Zend 
> Technologies
>     with Xdebug v2.2.5, Copyright (c) 2002-2014, by Derick Rethans
>
> When the “include” statement is RHS of an assignment (i.e., in expression 
> context), it is parsed like a function call, and it has a return value that 
> is assigned.  Likewise for “include_once”, “require”, and
> “require_once”.

I wouldn't say that it is parsed like a function call in any context.
The syntax is always

  T_INCLUDE expr

so provided the expr is bracketed, and is not followed by anything that
can be included in the parse of expr, then I'd say that is *looks* like
a function call.  Function call syntax binds very tightly, so the "+ 1"
in

  $v = strlen("abc") + 1;

does not disrupt the parse of the function call.  In contrast

  $v = include("abc") + 1;

is parsed very differently.

<snip>
-- 
Ben.

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Thread

Do you use extra parenthesis for include/require/echo? Matthew Carter <m@ahungry.com> - 2014-11-12 01:39 -0500
  Re: Do you use extra parenthesis for include/require/echo? "Christoph M. Becker" <cmbecker69@arcor.de> - 2014-11-13 00:33 +0100
  Re: Do you use extra parenthesis for include/require/echo? Jerry Stuckle <jstucklex@attglobal.net> - 2014-11-12 22:32 -0500
  Re: Do you use extra parenthesis for include/require/echo? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-11-13 11:48 +0000
    Re: Do you use extra parenthesis for include/require/echo? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-11-13 22:03 +0100
      Re: Do you use extra parenthesis for include/require/echo? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-11-13 23:18 +0000
        Re: Do you use extra parenthesis for include/require/echo? Jerry Stuckle <jstucklex@attglobal.net> - 2014-11-13 21:08 -0500
  Re: Do you use extra parenthesis for include/require/echo? crankypuss <crankypuss@nomail.invalid> - 2014-11-14 02:15 -0700

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