Many are tempted to try to eliminate many frequently-invalid
mail addresses with a simple regex, such as
-C</^[\w.-]+\@([\w.-]\.)+\w+$/>. It's a very bad idea. However,
+C</^[\w.-]+\@([\w.-]+\.)+\w+$/>. It's a very bad idea. However,
this also throws out many valid ones, and says nothing about
potential deliverability, so is not suggested. Instead, see
http://www.perl.com/CPAN/authors/Tom_Christiansen/scripts/ckaddr.gz ,