What is the definition of "legacy code"? [duplicate]

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P开发者_如何学JAVAossible Duplicate:

What makes code legacy?

What is the definition of "legacy code"?

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Channeling Michael Feathers: Code without tests.

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I can't remember where I saw the expression (Pragmatic Programmer?) but one way to think about it is code is legacy code as soon as it's written.

Generally it's referred to code that gets inherited by a team or a programmer from somewhere else (external or internal).

I prefer the former definition, though. :)

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Code someone else written (usually someone no longer available for any contact), but you must deal with it now.

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Code written by others or under a previous language, architecture, methodology, or framework that pertains to the current project.

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I would say that legacy code is (usually old) code that can be rewritten using better programming techniques or languages. Legacy code usually is not easily rewritten because of dependencies on that code.