Core

What is your opinion about introducing a TYPO3 Context?

This would imply:

• Add a TYPO3_CONTEXT constant
• The constant could be set by either simply setting the constant or by a PHP Environment variable or by PHP configuration.

# Computes Context
if (!defined('TYPO3_CONTEXT')) {
    if (getenv('TYPO3_CONTEXT')) {
        define('TYPO3_CONTEXT', getenv('TYPO3_CONTEXT'));
    } elseif (ini_get('TYPO3_ENV')) {
        define('TYPO3_CONTEXT', ini_get('TYPO3_CONTEXT'));
    } else {
        define('TYPO3_CONTEXT', 'Production');
    }
}

• TYPO3 would automatically load FooConfiguration.php if Foo is the Context name
• Add a new TypoScript condition for convenience

  [context = Foo]
  [end]

• Display a possible message in the BE Header of the current Context (should be only displayed if the Context is not production).
• The Core could possibly ship some default presets for particular context (e.g. Development)

The default Context would be "Production" to stay backwards compatible.