That depends on the code and on how "deep" you need to know it... I propose the following order:

  1. read the documentation (user manual, requirements, architecture, design)
  2. try to understand the related module-testcases
  3. read the comments inside the code
  4. read the code itself
  5. execute the code with debug-output, possibly alter the code and determine why which module-testcase fails
If the documentation is sparse, you might use re-engineering-tools like doxygen, or this resource for regular expressions.

Good luck (especially if you don't have documentation nor comments ;-)

Rata

In reply to Re: best way to understand existing perl code by Ratazong
in thread best way to understand existing perl code by balakrishnan

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