Hello,
I want to write a script that can check if a variable's value is numeric or not.
In perlfaq I came across this:
if (/\D/)            { print "has nondigits\n" }
    if (/^\d+$/)         { print "is a whole number\n" }
    if (/^-?\d+$/)       { print "is an integer\n" }
    if (/^[+-]?\d+$/)    { print "is a +/- integer\n" }
    if (/^-?\d+\.?\d*$/) { print "is a real number\n" }
    if (/^-?(?:\d+(?:\.\d*)?|\.\d+)$/) { print "is a decimal number\n"
+ }
    if (/^([+-]?)(?=\d|\.\d)\d*(\.\d*)?([Ee]([+-]?\d+))?$/)
            { print "a C float\n" }

[download]

Does this cover (i,e. exclude as wrong) examples like -.5 or 16F, etc?

In reply to variable has numeric value? by Anonymous Monk

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