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Re^2: check bind_columns for undefined values

by Anonymous Monk
on Feb 12, 2013 at 00:35 UTC ( #1018268=note: print w/ replies, xml ) Need Help??


in reply to Re: check bind_columns for undefined values
in thread check bind_columns for undefined values

Hi, Thanks for the Map idea, I'm new to perl (but not other similar languages).
Can someone explain why the example:

map { $$_ = "null" if (!defined $$_); } @list_of_refs_to_vars_to_bind;

...uses $$_ when I would expect it to use $_ - i've googled round and round but haven't found an explanation yet.

many thanks
jonathan


Comment on Re^2: check bind_columns for undefined values
Re^3: check bind_columns for undefined values
by ww (Bishop) on Feb 12, 2013 at 02:51 UTC
    A decent tut on reference/dereference -- such as those found in Tutorials right here in the Monastery -- should make the answer clear.

    If you didn't program your executable by toggling in binary, it wasn't really programming!

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