Hullo,
I've been reading an online tutorial that illustrates a simple substitution of "them" for "us" in the following string: 
$_='Us ? The bus usually waits for us, unless the driver forgets us.';

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The tutorial's solution is the following: 
$_='Us ? The bus usually waits for us, unless the driver forgets us.';
print "$_\n";
s/\b([Uu])s(\W)/chr(ord($1)-1).hem.$2/eg;
print "$_\n";

[download]
This works, but when I got to thinking about it... 
$_='Us? The bus usually waits for us, unless the driver forgets us.';
print "$_\n";
s/\bus\b/them/ig;
print "$_\n";

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also works and seems simpler to a newbie like me. I guess I'm just wondering if there's something about substitutions that I don't know yet which makes the simpler solution 'bad practice' or sloppy programming? I get the sense that the tutorial chose the solution it did based on something I don't yet know about regex's, but I can't figure out what that is.
Any guidance greatly apreciated.
-d4vis
#!/usr/bin/fnord

In reply to a simple substitution question by d4vis

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