Regular Expressions

Multipliers

• An item can be preceeded by a range of number of matches desired.
• For example, if you want to match from 5 to 10 instances of the "x" character, you would use the construct /x{5,10}/ .
• Example:
  

  $theVar = "This is a test.  Beeeeeeeeeeeeeeep";
  if ($theVar =~ /e{5,100}p$/) {
      (print "Match One\n");  # Would Match
  }
  if ($theVar =~ /e{100,120}p$/ /) {
      (print "Match Two\n");  # Would Not Match
  }
  

• If you only supply the first argument, the item must be matched exactly that number of times. For example, /be{2}p/ will only match the string "beep", not the string "bep" or "beeep".
• If you supply the first argument followed by a comma, but no second argument, then the item must be matched that many times or more. The second argument effectively defaults to infinity. For example, /be{2,}p/ will match the string "beep", "beep", "beeeeeeeep", etc.
• Note that {0,} is the same as *.
• Note that {1,} is the same as +.
• Note that {0,1} is the same as ?.
• Note that {1} is the same as nothing (no change).