If you just want to know whether it exists you have little choice but to grovel over @INC.

If you try to eval "use Some::Module" then the module will be loaded and any side-effects it has (such as exporting) will happen.

I suppose if you were feeling particularly crazy you could try something like this ... 

print 'the module exists' if(!system("perl -MSome::Module -e exit"));

[download]
but if I saw code like that in production I'm afraid I'd have to shoot you.

In reply to Re: Testing for a module's presence by DrHyde
in thread Testing for a module's presence by Anonymous Monk

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