This is not really an answer to your question, (and perhaps this would be better posted to snippets) but here is the csh alias I wrote ages ago to be my command line calculator, that I thought you might find useful. 

alias  calc  perl -e 'print  (!*) ; '

[download]

Usage: 

calc 7+7
or 
calc (24+11)*(8**2)

-monkfish (The Fishy Monk)

In reply to Re: extract an operator from a string by monkfish
in thread extract an operator from a string by Anonymous Monk

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