You can always check for optional spaces where needed by using \s* to check for 0 or more whitescape characters: 
  $s =~ /(\d+)(?:to|thru|up to|\s*-\s*)(\d+)/;

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What does your regex/string parsing code look like right now?

In reply to Re: extract numbers from unformatted text strings by davidrw
in thread extract numbers from unformatted text strings by punch_card_don

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