Hello,

I'm looking for criticism of my regular expression that looks for a number to be >= 0 and < 1 (i.e. 0, 0.00001, and .99999 are OK but 1, -0.00001, and -1 are NOT OK). I'm using the RE to untaint a number from a CGI form. The regex seems to work and is based on a regex in PerlFaq4 that matches decimal numbers. Here is the code in my CGI script that handles the untainting.

my ($num) = $_num =~  /^(0(\.\d+)?|\.\d+)$/;

Please comment on the accuracy and if there is a better way to do it.

Thank you,

lupey

<bold>Update</bold> Thank you everybody for your suggestions. I seem to like tlm's answer the best. I didn't realize that I could separate tainting from checking the numerical properties of a scalar.

In reply to Match number >= 0 and <1 by lupey

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