global errors: define or array ?

ruach

I am working on a medium sized portal. As I have been working on it I noticed that I am often having to send the same message to users again and again, eg 'You must login to view this page' or 'You do not have sufficient permissions to view this page' I an effort to be consistent I think it is time to store these messages in some kind of variable so that they are always the same every where.

My question to the community is what is the best way to do that.

The two alternatives I have come up with are:
1) define a bunch of constants i.e.

define('MUST_LOGIN', 'You must login to view this page');

2) use a global array i.e.

global $gStd_errors;
$gStd_errors = array('MUST_LOGIN'=>'You must login to view this page');

I like the define style because it is less cumbersome, in my opinion, than referencing a giant array, and may be faster depending on how large the array gets over time. I dislike this method because it clutters the already messy name space, and as time goes on I could end up with many, many of these constants. Advantages of using the array include, that I would be able at any time to see all the error I have defined.

At any rate I'm interested to see what you all think and what you've done on your own projects.

thanks
-Matthew

Merve

Either way, it doesn't really matter, in my opinion. The only recommendation I have is that you put all these constants or variables in external file which you can include. (But you were probably going to do that anyway.)

devinemke

i usually use arrays for this type of thing. i always have a common.php file which is included on every page for all common variables and functions:

$errors = array(
	'MUST_LOGIN' => 'You must login to view this page',
	'DB_DOWN' => 'Our database is currently unavaliable',
	'MAINTAINACE' => 'This page is currently down for maintainance'
);

then you can refer to it like this:

if (!$db_connect) {echo $GLOBALS['errors']['DB_DOWN'];}

the point of using the $GLOBALS syntax is that it will work everywhere, even inside functions, without having to declare $errors global within each function.

Weedpacket

I'd tend towards defining them as constants myself; it makes for much less code when using them (you can just have $message = MUST_LOGIN; instead of something like $message = $GLOBALS['messages']['MUST_LOGIN'];. There may also be a slight speed advantage. You can't write echo "MUST_LOGIN"; and have it work, but echo "{$GLOBALS[messages][MUST_LOGIN]}"; is more prone to typos and is measureably slower than echo "".MUST_LOGIN."".

I'd also put them all in a single separate file: (a) access is equally easy from any script that may use them, and (b) it becomes possible to have different sets of the messages (for different languages perhaps) in separate files and then decide at runtime which set to use simply by deciding which file to include.