Why not use a regexp? Something like ... 
unless ($foo =~ /^\-?\d*\.?\d*$/) {
   # do something
}

[download]
should do the trick.

Hope that helps.

-- Foxcub
#include www.liquidfusion.org.uk

Update: Doh, updated regexp to something that stands a chance in hell of actually working .. (thanks, antirice)

In reply to Re: numeric comparison by Tanalis
in thread numeric comparison by hotshot

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