why sending regexps via email is a bad idea

gistfile1.js

// client attempts to send a regexp in the body of an email message. it 
// didn't work. the "file:///" was the telltale sign something was wrong.
// 
// the irony here, of course, is that it's a regexp for validating email 
// addresses. (and what a regexp it is!)

// pasted into email body in outlook (FAIL!)
REGEX_EMAIL     = new RegExp("^([^()<>@,;:\\\\\".\\s\\x00-\\x1F\\x7F\\[\\]]+|\"([^\\\\\"\\x0D]|\\\\.)*\<file:///\\x0D]|\.)*\>")(\\.([^()<>@,;:\\\\\".\\s\\x00-\\x1F\\x7F\\[\\]]+|\"([^\\\\\"\\x0D]|\\\\.)*\"))*@([abcdefghijklmnopqrstuvwxyz0123456789]([-abcdefghijklmnopqrstuvwxyz0123456789]*[abcdefghijklmnopqrstuvwxyz0123456789])?)((\\.([abcdefghijklmnopqrstuvwxyz0123456789]([-abcdefghijklmnopqrstuvwxyz0123456789]*[abcdefghijklmnopqrstuvwxyz0123456789])?))*)(\\.([abcdefghijklmnopqrstuvwxyz0123456789]{2}|com|edu|gov|int|mil|net|org|biz|info|name|pro|aero|coop|museum|cat|jobs|mobi|tel|travel|xxx))$<file:///\\.([%5e()%3c%3e@,;:\%22.\s\x00-\x1F\x7F\%5b\%5d%5d+|\%22(%5b%5e\%22\x0D%5d|\.)*\%22))*@(%5babcdefghijklmnopqrstuvwxyz0123456789%5d(%5b-abcdefghijklmnopqrstuvwxyz0123456789%5d*%5babcdefghijklmnopqrstuvwxyz0123456789%5d)%3f)((\.(%5babcdefghijklmnopqrstuvwxyz0123456789%5d(%5b-abcdefghijklmnopqrstuvwxyz0123456789%5d*%5babcdefghijklmnopqrstuvwxyz0123456789%5d)%3f))*)(\.(%5babcdefghijklmnopqrstuvwxyz0123456789%5d%7b2%7d|com|edu|gov|int|mil|net|org|biz|info|name|pro|aero|coop|museum|cat|jobs|mobi|tel|travel|xxx))$>", "i"); // Note: for some reason [a-z], under some engines, behaves as \w (i.e. [_a-z])

// included as an attachment (yay!)
REGEX_EMAIL     = new RegExp("^([^()<>@,;:\\\\\".\\s\\x00-\\x1F\\x7F\\[\\]]+|\"([^\\\\\"\\x0D]|\\\\.)*\")(\\.([^()<>@,;:\\\\\".\\s\\x00-\\x1F\\x7F\\[\\]]+|\"([^\\\\\"\\x0D]|\\\\.)*\"))*@([abcdefghijklmnopqrstuvwxyz0123456789]([-abcdefghijklmnopqrstuvwxyz0123456789]*[abcdefghijklmnopqrstuvwxyz0123456789])?)((\\.([abcdefghijklmnopqrstuvwxyz0123456789]([-abcdefghijklmnopqrstuvwxyz0123456789]*[abcdefghijklmnopqrstuvwxyz0123456789])?))*)(\\.([abcdefghijklmnopqrstuvwxyz0123456789]{2}|com|edu|gov|int|mil|net|org|biz|info|name|pro|aero|coop|museum|cat|jobs|mobi|tel|travel|xxx))$", "i"); // Note: for some reason [a-z], under some engines, behaves as \w (i.e. [_a-z])