Command line switches are handy for some tasks, like -l and -n, which let you write the whole thing in one rather short line: 

C:\>perl -lne "print m/^\d{5}$/ ? ' OK' : ' Fail'"
5
 Fail
12345
 OK
123
 Fail
Hello
 Fail
3.141
 Fail
^Z

[download]

cheers

tachyon

In reply to Re: compare stdin for a number by tachyon
in thread compare stdin for a number by anoxer

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