It's not particularly pretty, but here's a solution using substr and a regular expression: 
if (length $word > 45) {
  my $forty_sixth = substr($word, 45, 1);
  $word = substr($word, 0, 45);
  $word =~ s/\s*\w*\z// if $forty_sixth =~ /\w/;
}

[download]

Update: For some reason I was thinking about this while trying to get to sleep last night. My solution will fail to trim whitespace in the case where the 45th and 46th chars are both whitespace. Also, I should know better than to write a substitution expression that can match the empty string. Here's a revised version that should work correctly: 

if (length $word > 45) {
  my $forty_sixth = substr($word, 45, 1);
  $word = substr($word, 0, 45);
  $word =~ s/\w+\z// if $forty_sixth =~ /^\w/;
  $word =~ s/\s+\z//;
}

[download]

In reply to Re: regexp word break help by thelenm
in thread regexp word break help by nop

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