| Copyright | (c) Eric Mertens 2023 |
|---|---|
| License | ISC |
| Maintainer | emertens@gmail.com |
| Safe Haskell | Safe-Inferred |
| Language | Haskell2010 |
Toml.Lexer
Description
This module parses a TOML file into a lazy sequence of tokens. The lexer is aware of nested brackets and equals signs in order to handle TOML's context-sensitive lexing requirements. This context enables the lexer to distinguish between bare keys and various values like: floating-point literals, integer literals, and date literals.
This module uses actions and lexical hooks defined in LexerUtils.
Synopsis
- data Context
- scanToken :: Context -> Located String -> Either (Located String) (Located Token, Located String)
- lexValue :: String -> Either String Token
- data Token
- = TokTrue
- | TokFalse
- | TokComma
- | TokEquals
- | TokNewline
- | TokPeriod
- | TokSquareO
- | TokSquareC
- | Tok2SquareO
- | Tok2SquareC
- | TokCurlyO
- | TokCurlyC
- | TokBareKey String
- | TokString String
- | TokMlString String
- | TokInteger !Integer
- | TokFloat !Double
- | TokOffsetDateTime !ZonedTime
- | TokLocalDateTime !LocalTime
- | TokLocalDate !Day
- | TokLocalTime !TimeOfDay
- | TokEOF
Documentation
Representation of the current lexer state.
Constructors
| TopContext | top-level where |
| TableContext | inline table - lex key names |
| ValueContext | value lexer - lex number literals |
| MlBstrContext Position [String] | multiline basic string: position of opening delimiter and list of fragments |
| BstrContext Position [String] | basic string: position of opening delimiter and list of fragments |
| MlLstrContext Position [String] | multiline literal string: position of opening delimiter and list of fragments |
| LstrContext Position [String] | literal string: position of opening delimiter and list of fragments |
scanToken :: Context -> Located String -> Either (Located String) (Located Token, Located String) Source #
Get the next token from a located string. This function can be total because one of the possible token outputs is an error token.
lexValue :: String -> Either String Token Source #
Lex a single token in a value context. This is mostly useful for testing.
Lexical token
Constructors
| TokTrue | true |
| TokFalse | false |
| TokComma | ',' |
| TokEquals | '=' |
| TokNewline | end-of-line |
| TokPeriod | |
| TokSquareO | '[' |
| TokSquareC | ']' |
| Tok2SquareO | '[[' |
| Tok2SquareC | ']]' |
| TokCurlyO | '{' |
| TokCurlyC | '}' |
| TokBareKey String | bare key |
| TokString String | string literal |
| TokMlString String | multiline string literal |
| TokInteger !Integer | integer literal |
| TokFloat !Double | floating-point literal |
| TokOffsetDateTime !ZonedTime | date-time with timezone offset |
| TokLocalDateTime !LocalTime | local date-time |
| TokLocalDate !Day | local date |
| TokLocalTime !TimeOfDay | local time |
| TokEOF | end-of-input |