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@NogDogAug 13.2005 — #
I seem to recall that PHP does not allow this, but I'll have to look into it to be sure, as that's a good idea.@NogDogAug 13.2005 — #
Yes. And I've confirmed by experimentation that you can not redefine a function.
Maybe a follow-up article in the works with some of the ideas here? I think I want to avoid introducing too much in one article.
Thanks to all for the feedback.@NogDogAug 15.2005 — #
This inspired me to come up with the following function:
Now all I need to do is incude() it into any script, and if I want to run in debug mode (have any errors reported directly to the normal output) just define a constant DEBUG as TRUE; otherwise it will run in non-debug mode, outputting all error text to the log file:
@NogDogAug 16.2005 — #Hmm...maybe I'll add...
...to my include file, then I can just call the error function as...
Jeff's idea of two functions has some merit, too, maybe actually calling them warn() and error(). Guess I just have to decide which way I prefer: one function with 2 parameters, or two functions with one parameter.
Defensive Coding
I’ve put together a first draft on a little article about defensive coding in PHP. I’d appreciate any feedback on the content: does it make sense, are the examples clear, any glaring omissions, etc.? I’m not worried about things like spelling and grammar at this point, I’ll clean that up later.
Thanks
And here’s the article: [url]http://www.charles-reace.com/article.html
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@NogDogAug 13.2005 — #I'm not up on my PHP, but are you able to override the functionality of core functions? For instance, instead of changing every single die to error, could you instead define die to do something different?[/QUOTE]
I seem to recall that PHP does not allow this, but I'll have to look into it to be sure, as that's a good idea.
0
@NogDogAug 13.2005 — #Instead of using die() at the coding stage and changing later you could use error() but have:
[code=php]function error($error)
{
die($error);
}[/code]
This would save changing die() to error() after debugging has finished. All that would be needed is changing the above function to your function.
Does this make any sense?[/QUOTE]
Yes. And I've confirmed by experimentation that you can not redefine a function.
Maybe a follow-up article in the works with some of the ideas here? I think I want to avoid introducing too much in one article.
Thanks to all for the feedback.
0
@NogDogAug 15.2005 — #Instead of using die() at the coding stage and changing later you could use error() but have:
[code=php]function error($error)
{
die($error);
}[/code]
This would save changing die() to error() after debugging has finished. All that would be needed is changing the above function to your function.
Does this make any sense?[/QUOTE]
This inspired me to come up with the following function:
[code=php]
function error($text, $fatal = FALSE)
{
if(!defined('DEBUG') or DEBUG == FALSE) # not in debug mode
{
# ouput error text to log file:
$path = "C:\"; # specify where log files will be saved
$this = array_pop(explode("/", $_SERVER['PHP_SELF']));
$file = "$path$this.log";
error_log(date("Y/m/d-h:m:s") . " --> $textn", 3, $file);
if($fatal)
{
$msg = <<<EOD
<p class="error">We're sorry, but an unrecoverable error occurred processing
your request. If this problem persists, please contact the
<a href="mailto:{$_SERVER['SERVER_ADMIN']}">webmaster</a>.</p>
EOD;
die($msg);
}
}
else # in debug mode
{
if($fatal)
{
die("<pre>ERROR: $text</pre>");
}
else # not fatal, so just output error text
{
echo("<pre>ERROR: $text</pre>");
}
}
}
[/code]Now all I need to do is incude() it into any script, and if I want to run in debug mode (have any errors reported directly to the normal output) just define a constant DEBUG as TRUE; otherwise it will run in non-debug mode, outputting all error text to the log file:
[code=php]
include "include.php"; # file that includes error() function
define('DEBUG', TRUE); # run this script in debug mode
# ... rest of script follows
# sample error situation:
mysql_query($query) or error("Query failed: " . mysql_error(), TRUE);
[/code]0
@NogDogAug 16.2005 — #Hmm...maybe I'll add...[code=php]
define('FATAL', TRUE);
define('NONFATAL', FALSE);
[/code]...to my include file, then I can just call the error function as...
[code=php]
error("error message", FATAL);
# or #
error("error message", NONFATAL);
[/code]Jeff's idea of two functions has some merit, too, maybe actually calling them warn() and error(). Guess I just have to decide which way I prefer: one function with 2 parameters, or two functions with one parameter.