Why is it, that a lot of PHP developers, seem to detest the idea of fail-fast?
Fail-fast has a great deal going for it. Yet PHP continues to fly in the face of overwhelming evidence, and suggest that it's a bad idea!
Even the manual pages, say things like:
Enabling E_NOTICE during development has some benefits. For debugging purposes: NOTICE messages will warn you about possible bugs in your code.
This implies that E_NOTICE in production is not desirable! I find the opposite to be true. Errors are more likely to happen in production (because silly users use your app, and obnoxious robots hit your site etc), so you REALLY want to know about them. Even the smallest things, that E_NOTICE shows, are usually very siginificant.
In other languages, things that make E_NOTICE in PHP, often cause exceptions to be thrown (incidentally, I normally have my error handler throw exceptions in response to E_NOTICE or anything higher). The most common example is a missing key in an associative array.
Then open source applications[1], typically disable E_NOTICE and/or E_WARNING, because otherwise they'd create so many that the server would be significantly impeded just writing the error log!
Fail-fast is, IMHO, extremely good. All errors, warnings and notices should be enabled at all times in development AND production environments.
An E_NOTICE may indicate a bug which will subsequently cause data corruption - therefore, the application MUST NOT CHARGE HEADLONG INTO DESTRUCTION.
The old "oh, an error happened, but who cares, let's continue anyway!" days are long gone for me.
Mark
[1] Wordpress 2.0.1, wp-settings.php lines 65-66:
// Change to E_ALL for development/debugging
error_reporting(E_ALL ^ E_NOTICE);
