Re: [PHP] Constants in strings
On 06/07/11 17:33, Robert Williams wrote: Where I've made most use of heredocs is when I want to do nothing but define a bunch of long strings in one file. I find the most useful thing about heredocs is that they don't care about quotation marks, so I often use them for SQL statements where I might have a mixture of ' and eg. $sql =EoSQL SELECT foo AS Foo FROM Bar WHERE baz='quux' EoSQL; -- Peter Ford, Developer phone: 01580 89 fax: 01580 893399 Justcroft International Ltd. www.justcroft.com Justcroft House, High Street, Staplehurst, Kent TN12 0AH United Kingdom Registered in England and Wales: 2297906 Registered office: Stag Gates House, 63/64 The Avenue, Southampton SO17 1XS -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Constants in strings
On 7/6/2011 7:07 AM, Dave Wilson wrote:
Output - {XYZ}
Attempt 2:
?php
define ('XYZ','ABC');
echo {{XYZ}}\n;
?
Output - {{XYZ}}
No luck there. I did encounter one oddity though:
?php
define ('XYZ','ABC');
echo {${XYZ}}\n;
?
Output:
PHP Notice: Undefined variable: ABC in /home/wilsond/testScripts/l7.php
on line 3
Which appears to mean that PHP is able to pick up the value of the
constant and try to access a variable with that name.
Any ideas?
echo XYZ . \n;
--Curtis
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Re: [PHP] Constants in strings
On Wed, Jul 6, 2011 at 12:07 PM, Dave Wilson dai_bac...@hotmail.com wrote:
Hi all,
OK. We all know that constants cannot be accessed directly via their name
in double-quoted or heredoc strings. I knew this already but a read of
the PHP manual got me thinking.
The manual states that to get the $$ value of a variable, the form
{${var}} should be used. Therefore, I wondered if something similar
would work for constants.
Attempt 1 (just to be sure):
?php
define ('XYZ','ABC');
echo {XYZ}\n;
?
Output - {XYZ}
Attempt 2:
?php
define ('XYZ','ABC');
echo {{XYZ}}\n;
?
Output - {{XYZ}}
No luck there. I did encounter one oddity though:
?php
define ('XYZ','ABC');
echo {${XYZ}}\n;
?
Output:
PHP Notice: Undefined variable: ABC in /home/wilsond/testScripts/l7.php
on line 3
Which appears to mean that PHP is able to pick up the value of the
constant and try to access a variable with that name.
Any ideas?
My guess is that the preceding $ causes PHP to interpret the next token
{XYZ} as a variable or a constant, but without that preceding $ it has no
way to know you're trying to use a constant. As Curtis points out, the only
way to insert a constant into a string is through concatenation.
-Stuart
--
Stuart Dallas
3ft9 Ltd
http://3ft9.com/
Re: [PHP] Constants in strings
Any ideas? echo XYZ . \n; --Curtis -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php Which doesn't answer the original question Dave asked... Thanks, Ash http://www.ashleysheridan.co.uk -- Sent from my Android phone with K-9 Mail. Please excuse my brevity. -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Constants in strings
On Wed, 06 Jul 2011 12:56:21 +0100, Stuart Dallas wrote:
My guess is that the preceding $ causes PHP to interpret the next token
{XYZ} as a variable or a constant, but without that preceding $ it has
no way to know you're trying to use a constant. As Curtis points out,
the only way to insert a constant into a string is through
concatenation.
-Stuart
OK. I should have made myself clearer - I was making an observation with
regards to constant parsing in strings rather than looking for advice. My
bad.
My third example showed that {${XYZ}} would echo the value of the
variable called the value of XYZ:
?php
define ('XYZ','ABC');
$ABC=huh!;
echo {${XYZ}}\n;
?
Output - huh!
We could easily re-write the 'echo' line above to be:
echo {${constant('XYZ'}}\n;
But my example shows that PHP *is* accessing the value of a constant
without any jiggery-pokery or hacks (e.g. http://www.php.net/manual/en/
language.types.string.php#91628) as it is retrieving the value of ABC
from the XYZ constant and then looking for a variable of that name.
I admit that I'm no C coder but it may be possible (note, the word may)
that a change of code within the PHP source tree will allow us to use
something like echo {{XYZ}} to access the constant value.
Cheers
Dave
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RE: [PHP] Constants in strings
-Original Message-
From: Dave Wilson [mailto:dai_bac...@hotmail.com]
Sent: Wednesday, July 06, 2011 10:11 AM
To: php-general@lists.php.net
Subject: Re: [PHP] Constants in strings
On Wed, 06 Jul 2011 12:56:21 +0100, Stuart Dallas wrote:
My guess is that the preceding $ causes PHP to interpret the next
token
{XYZ} as a variable or a constant, but without that preceding $ it
has
no way to know you're trying to use a constant. As Curtis points out,
the only way to insert a constant into a string is through
concatenation.
-Stuart
OK. I should have made myself clearer - I was making an observation
with
regards to constant parsing in strings rather than looking for advice.
My
bad.
My third example showed that {${XYZ}} would echo the value of the
variable called the value of XYZ:
?php
define ('XYZ','ABC');
$ABC=huh!;
echo {${XYZ}}\n;
?
Output - huh!
We could easily re-write the 'echo' line above to be:
echo {${constant('XYZ'}}\n;
But my example shows that PHP *is* accessing the value of a constant
without any jiggery-pokery or hacks (e.g. http://www.php.net/manual/en/
language.types.string.php#91628) as it is retrieving the value of ABC
from the XYZ constant and then looking for a variable of that name.
I admit that I'm no C coder but it may be possible (note, the word
may)
that a change of code within the PHP source tree will allow us to use
something like echo {{XYZ}} to access the constant value.
Cheers
Dave
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define('DIR_JAVA', '/js/');
When you need to use the JavaScript directory you can do this.
script src=?php echo DIR_JAVA . 'jquery-1.5.1.js';?/script
There is no true need for the curly brackets to echo out the value of the
constant.
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RE: [PHP] Constants in strings
define('DIR_JAVA', '/js/');
When you need to use the JavaScript directory you can do this.
script src=?php echo DIR_JAVA . 'jquery-1.5.1.js';?/script
There is no true need for the curly brackets to echo out the value of
the constant.
Except for when you're using heredoc, much like in the OPs first post...
Thanks,
Ash
http://www.ashleysheridan.co.uk
--
Sent from my Android phone with K-9 Mail. Please excuse my brevity.
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RE: [PHP] Constants in strings
Yeah, that was my answer and I was rebuked for that.
ad...@buskirkgraphics.com wrote:
-Original
Message-
From: Dave Wilson
[mailto:dai_bac...@hotmail.com]
Sent: Wednesday, July 06,
2011 10:11 AM
To: php-general@lists.php.net
Subject: Re: [PHP] Constants in strings
On
Wed, 06 Jul 2011 12:56:21 +0100, Stuart Dallas wrote:
My guess is that the preceding $ causes PHP to interpret the next
token
{XYZ} as a variable or a
constant, but without that preceding $ it
has
no way to know you're trying to use a constant. As Curtis points
out,
the only way to insert a constant into a string is
through
concatenation.
-Stuart
OK. I should have made myself
clearer - I was making an observation
with
regards to constant parsing in strings rather than looking for advice.
My
bad.
My third
example showed that {${XYZ}} would echo the value of the
variable called the value of XYZ:
?php
define ('XYZ','ABC');
$ABC=huh!;
echo
{${XYZ}}\n;
?
Output - huh!
We could easily re-write the 'echo' line above to
be:
echo {${constant('XYZ'}}\n;
But my example shows that PHP *is* accessing the value of a
constant
without any jiggery-pokery or hacks (e.g.
http://www.php.net/manual/en/
language.types.string.php#91628) as it is retrieving the value of ABC
from the XYZ constant and then looking for a variable of that
name.
I admit that I'm no C coder but it may
be possible (note, the word
may)
that a change of code within the PHP source tree will allow us to use
something like echo {{XYZ}} to access the constant
value.
Cheers
Dave
--
PHP
General Mailing List (http://www.php.net/)
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visit: http://www.php.net/unsub.php
define('DIR_JAVA', '/js/');
When you need to
use the JavaScript directory you can do this.
script
src=?php echo DIR_JAVA .
'jquery-1.5.1.js';?/script
There is no true need for the curly brackets to echo out the value of
the
constant.
--
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RE: [PHP] Constants in strings
-Original Message-
From: Ashley Sheridan [mailto:a...@ashleysheridan.co.uk]
Sent: Wednesday, July 06, 2011 10:49 AM
To: ad...@buskirkgraphics.com; 'Dave Wilson'; php-general@lists.php.net
Subject: RE: [PHP] Constants in strings
define('DIR_JAVA', '/js/');
When you need to use the JavaScript directory you can do this.
script src=?php echo DIR_JAVA . 'jquery-1.5.1.js';?/script
There is no true need for the curly brackets to echo out the value of
the constant.
Except for when you're using heredoc, much like in the OPs first
post...
Thanks,
Ash
http://www.ashleysheridan.co.uk
--
Sent from my Android phone with K-9 Mail. Please excuse my brevity.
Ash,
I have a few questions.
I use constants in my OOP and I never use the heredoc syntax. Now I am fearing
that I have not taken advantage of something.
My understanding of heredoc syntax as of 5.3 is just a string quoting right?
Is there an advantage of using the heredoc syntax over single quoted or double
quoted?
Examples:
Echo 'your constant for the javascript path is '.DIR_JAVA;
Echo EOT
Your constant for the JavaScript path is {{DIR_JAVA}}
EOT;
I fully understand the syntax but I do not understand the advantages of using
either.
Is it just a writing style, or is there an advantage to the way it processes,
speed or something?
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Re: [PHP] Constants in strings
On 2011-07-6 08:09, ad...@buskirkgraphics.com ad...@buskirkgraphics.com wrote: I use constants in my OOP and I never use the heredoc syntax. Now I am fearing that I have not taken advantage of something. My understanding of heredoc syntax as of 5.3 is just a string quoting right? Is there an advantage of using the heredoc syntax over single quoted or double quoted? I don't believe that a heredoc will perform significantly differently than a double-quoted string, as, from the parser's POV, they're essentially the same thing once you get past the step of extracting the entire string from the source. I've not verified this by reviewing the relevant source, however, nor have I benchmarked it. But, I'm willing to bit that even if there is a difference, it's so small that you're better off worrying about which will lead to easier code maintenance than worrying about performance (as is typically the case with such micro-optimization choices). In my view, what's important is how you use them. In particular, a heredoc can present a bit more cleanly when you're dealing with a large-ish chunk of text, as in, say, an e-mail message template. The main downside is that they will usually make a mess of code formatting, since the closing delimiter must be against the left margin. For this reason, I tend to prefer multi-line double-quoted strings over heredocs when I have meaningful indentation, as in a function or class method. Where I've made most use of heredocs is when I want to do nothing but define a bunch of long strings in one file. For example, I might create a file to define a set of related e-mail message templates: ?php $accountCreationSuccessfulMessage = EndSuccess Pellentesque habitant morbi tristique senectus et netus et malesuada fames ac turpis egestas. Vestibulum tortor quam, feugiat vitae, ultricies eget, tempor sit amet, ante. Donec eu libero sit amet quam egestas semper. Aenean ultricies mi vitae est. Mauris placerat eleifend leo. Quisque sit amet est et sapien ullamcorper pharetra. Vestibulum erat wisi, condimentum sed, commodo vitae, ornare sit amet, wisi. Aenean fermentum, elit eget tincidunt condimentum, eros ipsum rutrum orci, sagittis tempus lacus enim ac dui. Donec non enim in turpis pulvinar facilisis. Ut felis. EndSuccess $accountCreationFailedMessage = EndFailure Donec placerat. Nullam nibh dolor, blandit sed, fermentum id, imperdiet sit amet, neque. Nam mollis ultrices justo. Sed tempor. Sed vitae tellus. Etiam sem arcu, eleifend sit amet, gravida eget, porta at, wisi. Nam non lacus vitae ipsum viverra pretium. Phasellus massa. Fusce magna sem, gravida in, feugiat ac, molestie eget, wisi. Fusce consectetuer luctus ipsum. Vestibulum nunc. Suspendisse dignissim adipiscing libero. Integer leo. Sed pharetra ligula a dui. Quisque ipsum nibh, ullamcorper eget, pulvinar sed, posuere vitae, nulla. Sed varius nibh ut lacus. Curabitur fringilla. Nunc est ipsum, pretium quis, dapibus sed, varius non, lectus. Proin a quam. Praesent lacinia, eros quis aliquam porttitor, urna lacus volutpat urna, ut fermentum neque mi egestas dolor. EndFailure ? Of course, this is arguably as clean: ?php $accountCreationSuccessfulMessage = Pellentesque habitant morbi tristique senectus et netus et malesuada fames ac turpis egestas. Vestibulum tortor quam, feugiat vitae, ultricies eget, tempor sit amet, ante. Donec eu libero sit amet quam egestas semper. Aenean ultricies mi vitae est. Mauris placerat eleifend leo. Quisque sit amet est et sapien ullamcorper pharetra. Vestibulum erat wisi, condimentum sed, commodo vitae, ornare sit amet, wisi. Aenean fermentum, elit eget tincidunt condimentum, eros ipsum rutrum orci, sagittis tempus lacus enim ac dui. Donec non enim in turpis pulvinar facilisis. Ut felis. ; //$accountCreationSuccessfulMessage $accountCreationFailedMessage = Donec placerat. Nullam nibh dolor, blandit sed, fermentum id, imperdiet sit amet, neque. Nam mollis ultrices justo. Sed tempor. Sed vitae tellus. Etiam sem arcu, eleifend sit amet, gravida eget, porta at, wisi. Nam non lacus vitae ipsum viverra pretium. Phasellus massa. Fusce magna sem, gravida in, feugiat ac, molestie eget, wisi. Fusce consectetuer luctus ipsum. Vestibulum nunc. Suspendisse dignissim adipiscing libero. Integer leo. Sed pharetra ligula a dui. Quisque ipsum nibh, ullamcorper eget, pulvinar sed, posuere vitae, nulla. Sed varius nibh ut lacus. Curabitur fringilla. Nunc est ipsum, pretium quis, dapibus sed, varius non, lectus. Proin a quam. Praesent lacinia, eros quis aliquam porttitor, urna lacus volutpat urna, ut fermentum neque mi egestas dolor. ; //$accountCreationFailedMessage ? With the latter, there is the catch that you end up with leading and trailing line breaks, but those are easy enough to deal with, if desired. As to the original topic of this thread, it's long annoyed me that there's no easy way to use constants with interpolation. Since I find repeated concatenation extremely ugly and prone to
Re: [PHP] Constants in strings
I LOVE the heredocs tool. I only learned about it a couple of months ago - what a find! It makes generating my html for my web pages so much easier and allows me to include my php vars within the html with much less confusion and simplifies the intermixing of html and php vars - no more single quote, double quote and dot stuff in an html tag. Sure you have to put the closing tag in column 1 - a mere blip against the pros. -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Constants in strings
On 11-07-06 02:59 PM, Jim Giner wrote: I LOVE the heredocs tool. I only learned about it a couple of months ago - what a find! It makes generating my html for my web pages so much easier and allows me to include my php vars within the html with much less confusion and simplifies the intermixing of html and php vars - no more single quote, double quote and dot stuff in an html tag. Sure you have to put the closing tag in column 1 - a mere blip against the pros. With respect to putting the closing tag in column 1... I've found the following to be fairly unobtrusive: ?php $blah = _ Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. _; ? Cheers, Rob. -- E-Mail Disclaimer: Information contained in this message and any attached documents is considered confidential and legally protected. This message is intended solely for the addressee(s). Disclosure, copying, and distribution are prohibited unless authorized. -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
