Module: EmailAddressPatternMatchValidation

Defined in:

lib/email_address_pattern_match_validation.rb

Overview

EmailAddressPatternMatchValidation

Author

Joel Parker Henderson, joelparkerhenderson@gmail.com

Copyright

Copyright © 2006-2008 Joel Parker Henderson

License

CreativeCommons License, Non-commercial Share Alike

License

LGPL, GNU Lesser General Public License

Email address regex, to validate an email address using RFC 822.

This is a gem wrapper around tfletcher.com/lib/rfc822.rb

Example

if EmailAddressPattern=~'foo@bar.com'
  puts "found" 
else
  puts "not found"
end
=> found

To find an email address in a string, do the pattern match then use the result, which is the match’s string position:

Example of match position

match_position = EmailAddressPattern=~'foo@bar.com'
=> 0

match_position = EmailAddressPattern=~'... foo@bar.com ...'
=> 4

match_position = EmailAddressPattern=~'... hello world ...'
=> nil

To do an exact pattern match, use the EmailAddressExactPattern. This matches the entire string from start to end; in other words, the entire string must be one email address.

Example of exact pattern match

if EmailAddressExactPattern=~'foo@bar.com' 
  puts "found" 
else
  puts "not found"
end
=> found

if EmailAddressExactPattern=~'... foo@bar.com ...' 
  puts "found" 
else
  puts "not found"
end
=> not found

The exact pattern is especialy useful to validate an email address.

Example to validate an email address

def valid?(email_address)
  EmailAddressExactPattern=~email_address ? true : false
end

Constant Summary

EmailAddressQText =

'[^\\x0d\\x22\\x5c\\x80-\\xff]'

EmailAddressDText =

'[^\\x0d\\x5b-\\x5d\\x80-\\xff]'

EmailAddressAtom =

'[^\\x00-\\x20\\x22\\x28\\x29\\x2c\\x2e\\x3a-\\x3c\\x3e\\x40\\x5b-\\x5d\\x7f-\\xff]+'

EmailAddressQuotedPair =

'\\x5c[\\x00-\\x7f]'

EmailAddressDomainLiteral =

"\\x5b(?:#{EmailAddressDText}|#{EmailAddressQuotedPair})*\\x5d"

EmailAddressQuotedString =

"\\x22(?:#{EmailAddressQText}|#{EmailAddressQuotedPair})*\\x22"

EmailAddressDomainRef =

EmailAddressAtom

EmailAddressSubDomain =

"(?:#{EmailAddressDomainRef}|#{EmailAddressDomainLiteral})"

EmailAddressWord =

"(?:#{EmailAddressAtom}|#{EmailAddressQuotedString})"

EmailAddressDomain =

"#{EmailAddressSubDomain}(?:\\x2e#{EmailAddressSubDomain})*"

EmailAddressLocalPart =

"#{EmailAddressWord}(?:\\x2e#{EmailAddressWord})*"

EmailAddressSpec =

"#{EmailAddressLocalPart}\\x40#{EmailAddressDomain}"

EmailAddressPattern =

/#{EmailAddressSpec}/

EmailAddressExactPattern =

/\A#{EmailAddressSpec}\z/