Documentation

The external pattern syntax (ERE syntax)

Constructors

EEmpty
EGroup EPat	the group ( re )
EOr [EPat]	the union re\|re
EConcat [EPat]	the concantenation rere
EOpt EPat Bool	the option re?, the last boolean flag indicates whether it is greedy
EPlus EPat Bool	the plus re+
EStar EPat Bool	the star re*
EBound EPat Int (Maybe Int) Bool	re{1:10}
ECarat	the ^ NOTE:shouldn't this must be top level?
EDollar	the $
EDot	the any char .
EAny [Char]	the character class [ a-z ]
ENoneOf [Char]	the negative character class [^a-z]
EEscape Char	backslash char
EChar Char	the non-escaped char

Instances

Function hasGroup tests whether an external pattern has ( ... ) (i.e. variable patterns in the internal pattern)