Understanding PHP code - absolute path

Posted on 2009-07-15
Last Modified: 2013-12-13
I am working on a php web application. Trying to understand the path to files:
What does following code means?

img src="$$application_settings::base_path$$images/header.gif"

Why are there two dollar signs? (it's php 4.4.7)

Question by:awarraic
LVL 18

Expert Comment

by:Greg Alexander
ID: 24859409
I never use $$ but here is the explanation of it: 
LVL 48

Accepted Solution

hernst42 earned 250 total points
ID: 24859446
No this is template system. Somewhere you configure the value for application_settings::base_path and then in that file $$application_settings::base_path$$ is replaced by the template engine with the configured/calculated value. This has nothing to do with the $$ of php beasue you would get something like:

img src="foo::base_pathBAR/header.gif"

in your html

Author Comment

ID: 24859478
How do I make that header display?
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LVL 48

Assisted Solution

hernst42 earned 250 total points
ID: 24859561
> Why are there two dollar signs? (it's php 4.4.7)
beacuse the programmer defined that variables for his template engine are stored between $$ and $$. Could also be ## and ##

> How do I make that header display?
Configure the template engine correctly.
LVL 19

Expert Comment

ID: 24875584


$$image will create a "PHP variable" with the name CONTAINED in the variable $image.

so if:
$image = 'pictures';
$$image would reference a variable named $pictures

Wha you want is to just change it to:
img src="http://www.yourwebsite/com/images/header.gif" // path to header.gif

Open in new window

LVL 19

Expert Comment

ID: 24875587
Correction $$ will reference a variable based on the $variable

so if:
$image = 'pictures';
$image would reference a variable named $pictures

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