you also don't escape characters in a character class. your regex (once g is added for global) will strip back slash characters, as well as braces.

$_ = 'foo\bar(baz)'; print "Before: '$_'; ";
s/[\(\)]//g;         print "After: '$_'\n";
__END__
Before: 'foo\bar(baz)'; After: 'foo\barbaz'
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you also don't escape characters in a character class.

That's not very good advice. Sometimes you certainly do need to escape characters in a character class. Take the following for example:

$ perl -le '$_ = q/f!o@o#b$a%r^b&a*z/; s/[!@#$%^&*]//g; print'
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-sauoq
"My two cents aren't worth a dime.";

Or, even more drastical, see the difference in these lines:
perl -e '$_="bjzu-sbtz -abnzo-tbhze-rb zp-ebrzl- bhza-cbkze-r\n";s/[b-z]//g;print'
vs.
perl -e '$_="bjzu-sbtz -abnzo-tbhze-rb zp-ebrzl- bhza-cbkze-r\n";s/[b\-z]//g;print'


---

s$$([},&%#}/&/]+}%&{})*;#$&&s&&$^X.($'^"%]=\&(|?*{%
+.+=%;.#_}\&"^"-+%*).}%:##%}={~=~:.")&e&&s""`$''`"e

the hardest line to type correctly is: stty erase ^H

Type it as: stty erase ^V^H

Update: I missed the point, which was that you cannot backspace if backspace isn't set correctly.