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Monolog should be able to calculate a hash identifying a message. This would allows storing them in a storage when an error occur and flushing them in an handler only once instea dof having one message per request.
This should use the IntrospectionProcessor code and crc32 the output. The message and others can't be taken into consideration because they could be input or date-sensitive.
There is issue with this. Think for instance to the Symfony2 ExceptionListener. All exceptions are logged at the same line, so this will not be enough to determine if this is the same mesage.
Well, we could have another hash computation for Symfony2 that ignores the exception listener or something. But yeah I agree this could be problematic. It can wait until 1.1 anyway.