Is there a "fancy" Ruby way to check whether a local variable is both defined and evaluates to true without using ands and ors?

Posted by Steven Xu on Stack Overflow See other posts from Stack Overflow or by Steven Xu
Published on 2011-01-07T05:24:53Z Indexed on 2011/01/07 6:53 UTC
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ruby

This is quite a quick question. I currently use

do_this if (testvar ||= false)

Which works just fine.

But this approach unnerves me because while fast, it does not short-circuit like defined?(testvar) && testvar does, and it instantiates and assigns a value to a local variable that is subsequently never used, which seems inefficient.

I enjoy the very reasonable fact that instance variables are nil before assignment, but I'd like for the situation to be just as easy for local variables.

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Is there a "fancy" Ruby way to check whether a local variable is both defined and evaluates to true without using ands and ors? - Developer IT

Is there a "fancy" Ruby way to check whether a local variable is both defined and evaluates to true without using ands and ors?

ruby

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how to change ruby path from /usr/bin/ruby to /usr/local/bin/ruby

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