Too efficient? Execution efficiency, programming efficiency, or maintenance efficiency? There are many types. Using a regex may not always be as fast (in many cases it is faster -- try using index and substr to find word space), but in most instances they are more maintainable and more readable and faster to write. 
use Benchmark;
my $n = 1000;
open(STDERR,">/dev/null");
cmpthese (1000,
            {
              match => sub { local $_ = "abcde    " x $n;
                             print STDERR "$1\n" while /\G(.{1,80})/gs
+;
                           },
              swap  => sub { local $_ = "abcde    " x $n;
                             s/\G(.{1,80})/$1\n/gs;
                             print STDERR $_;
                           },
              subst => sub { local $a = "abcde    " x $n;
                             $b='';
                             $b .= substr( $a, 0, 80, '')."\n" while l
+ength($a) >80;
                             print STDERR "$b$a";
                           },
            });

[download]
Produces 
Benchmark: timing 1000 iterations of match, subst, swap...
     match:  1 wallclock secs ( 0.97 usr +  0.00 sys =  0.97 CPU) @ 10
+30.93/s (n=1000)
     subst:  1 wallclock secs ( 0.58 usr +  0.00 sys =  0.58 CPU) @ 17
+24.14/s (n=1000)
      swap:  1 wallclock secs ( 0.75 usr +  0.00 sys =  0.75 CPU) @ 13
+33.33/s (n=1000)
        Rate match  swap subst
match 1031/s    --  -23%  -40%
swap  1333/s   29%    --  -23%
subst 1724/s   67%   29%    --

[download]
A substr method is faster this time, but if it gets any more complex than that a regex will do just fine. If done once per script will you notice the difference between 1700 per second and 1300 per second? Maybe.

In reply to Re: Re:{4} how do I line-wrap while copying to stdout? by Rhandom
in thread how do I line-wrap while copying to stdout? by ams

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