Language.HaLex.RegExp

Empty	Empty Language
Epsilon	Empty String
Literal sy	Literals
Or (RegExp sy) (RegExp sy)	Disjuncion
Then (RegExp sy) (RegExp sy)	Sequence
Star (RegExp sy)	Repetition, possibly zero time
OneOrMore (RegExp sy)	One or more times (extended RegExp)
Optional (RegExp sy)	Optional (extended RegExp)

Instances

Show sy => Show (RegExp sy)

(Read sy, ??? sy) => Read (RegExp sy)

(Eq sy, ??? sy) => Eq (RegExp sy)

cataRegExp :: (re, re, re -> re -> re, re -> re, sy -> re, re -> re -> re, re -> re, re -> re) -> RegExp sy -> re

Catamorphism induced by the RegExp inductive data type

matchesRE

:: Eq sy
=> RegExp sy	(canonical) Regular Expression
-> [sy]	Input Symbols
-> Bool
Test whether a match can be found for the given regular expression in the given sequence of characters. The regular expression is assumed not to contain `OneOrMore` or `Optional`. See also `matches'`.

matches'

:: Eq sy
=> RegExp sy	Regular Expression
-> [sy]	Input Symbols
-> Bool
Test whether a match can be found for the given regular expression in the given sequence of characters. The regular expression is allowed to contain `OneOrMore` or `Optional`.

sizeRegExp

:: RegExp sy	Regular Expression
-> Int	Size
Compute the size of a regular expression. We define the size of a regular expression as the number of occurrences of symbols of the alfabeth and epsilon symbols

showRE

:: Show sy
=> RegExp sy	Regular Expression
-> [Char]	String-based Regular Expression
Print regular expression to String as a catamorphism. A straightforward (catamorphic) show function. (it produces too many brackets, making it difficult to read or understand the expression)

simplifyRegExp :: Eq sy => RegExp sy -> RegExp sy

Simplify regular expressions according to the algebra of regular expressions.

extREtoRE :: RegExp sy -> RegExp sy

Rewrite extended regular expressions to plain regular expression. This means that the OneOrMore and Optional constructors are normalized away.

Produced by Haddock version 0.6