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I am a web developer and at the moment am finding it hard to cope with long un-documented code written by previous developers in an organisation I work for. With the deadline gun always pointed at my forehead, it's doing my head in. I use aptana studio's search feature for some quick wins but it is becoming overwhelming to a point that I do not want to work with them anymore.
Is there any quick/proven approach that I can take to help me with a scenario like this?