If, in addition to using warnings with its very helpful message referred to in other replies, you had been using strict, Perl would never have let you make the mistake in the first place if you were using names other than $a and $b!

In reply to Re^3: ptkdb: 'my' variable in sub retains value between calls by Anonymous Monk
in thread ptkdb: 'my' variable in sub retains value between calls by leonidlm

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