Let me answer with a question of my own...

How does the variable know which values are okay?

That begs the answer, "I tell it." That implies you have a list of acceptable values, which you can also use to test against (probably with grep) later on. Follow?

In reply to Re: How do I restrict a variable to a range of values? by kwaping
in thread How do I restrict a variable to a range of values? by tphyahoo

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