That matches "SB00\n" and you said it shouldn't. Replace /$/ with /\z/ to get the stated desired behaviour.

\d can match more than 0-9. I presume you don't want to match arab digits.

That uses needless captures. Get rid of them. 

m/^(SB)(\d{1,2})$/i

[download]
should be 
m/^SB[0-9]{1,2}\z/i

[download]

In reply to Re^3: Noob Question - not sure what's wrong by ikegami
in thread Noob Question - not sure what's wrong by vishi

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