A very creative solution :)
Be sure to check out Roman if you didn't know it already. It can convert roman numbers both ways, and checks if your roman input is valid.

use Roman;
$calc = "II + II";
$calc =~ s/([MDCLXVI]+)/isroman($1) ? arabic($1) : $1/;
print eval $calc;

[download]

2;0 juerd@ouranos:~$ perl -e'undef christmas'
Segmentation fault
2;139 juerd@ouranos:~$

[download]

In reply to Re: Re: Adding 2 + 2 by Juerd
in thread Adding 2 + 2 by merlyn

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