RegExChar.MetaChar

AUTHOR

Dr. Alistair Ward

DESCRIPTION

• Implements ShortcutExpander Char, to implement some of the traditional Perl-style shortcuts:

\d

=> Any isDigit-character.

\D

=> Any non-isDigit character.

\s

=> Any isSpace-character.

\S

=> Any non-isSpace character.

\w

=> Any Data.Char.isWord letter.

\W

=> Any non-Data.Char.isWord letter.

• Enables one to compose concise regexen, containing any Char that's a member of one of these predefined sets.
• Though Meta is polymorphic, & the type-parameter can't be assumed to implement either Enum or Ord, Char actually does, so this module is able to implement ranges within a Bracket-expression.
• Defines specialised instances of Read & Show, to cope with Perl-style shortcuts, Posix Character-classes & Bracket-expression range-specifications.

TODO

Use Environment.getLocale. Regrettably, this returns in the IO-monad, & even it didn't, how does one pass that information to Read ?!

Types

Type-synonyms

newtype MetaChar

A specialised instance, encapsulated to permit tailored instance-declarations.

Constructors

MkMetaChar (Meta Char)

Instances

Eq MetaChar

Read MetaChar

Show MetaChar

Consumer MetaChar

SelfValidator MetaChar

Constants

Functions

metaCharParser :: Parser MetaChar

Builds a parser of traditional regex-syntax, which understands Char-specific concepts like Perl-style shortcuts & Posix Character-classes.

Accessors (Deconstructors)

deconstruct :: MetaChar -> Meta Char

Accessor.