In a nutshell, you can't.

In the same way, you cannot program your own expression form of map or grep (eg. @squares = map $_**2, 1 .. 10;).

Many of perl's built-ins cannot be directly emulated with Perl code.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

The start of some sanity?

In reply to Re: How can I re-program the exists function? by BrowserUk
in thread How can I re-program the exists function? by greengaroo

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