`Greed' is Often Misunderstood

• Consider "Hot XXX Action!" =~ s/X*//

/X*/

• It gets the empty string, not XXX

  • Even though XXX is longer

  • Because Perl starts at the leftmost position first

  • X* will match zero Xes.

  • At the leftmost position, there are zero Xes.

• Solution: Use X+ instead

• Maxim: ``Say what you mean!''

• People over-use *

• Many *'s should be + instead

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Copyright © 2002 M. J. Dominus