parsers

Scala parser combinator libraries collection.

About

This repository contains the following libraries:

• parsers-common: Common utilities for parser combinator.
• parsers-contparse: A parser combinator library with continuation passing style.
• parsers-funcparse: A basic functional parser combinator library.
• parsers-inlineparse: A faster parser combinator library with mutable state & inline expansion.
• parsers-stackparse: A stackless parser combinator library.

API

P[T] is parser type, Parsed[T] is result type, and the following method is parser executor:

def parse[T](input: String, p: P[T]): Parsed[T] = ...

You can create P[T] by the following primitives, and combinate parsers by the following combinators.

Primitives

• "literal": just matches "literal".
• CharIn("abc"): matches a character contained in "abc".
• CharPred(isXXX): matches a character with which isXXX returns true.
• CharsWhileIn("abc") matches seqence of characters contained in "abc".
• CharsWhile(isXXX) matches sequence of characters with which isXXX returns true.
• AnyChar: matches an any character.
• Start: only matches at start position.
• End: only matches at end position.
• p.!: captures a string on p matching.

Combinators

• P(p): same as p, but it is lazy evaluated (for recursive parsers).
• Pass: succeeds with () value.
• Pass(v): succeeds with v.
• Fail: fails matching.
• Fail(msg): fails matching with msg.
• &?(p): matches when p is matched, but is does not consume any characters (positive look-ahead).
• &!(p): matches when p is not matched, but is does not consume any characters (negative look-ahead).
• p1 ~ p2: matches p1 and then matches p2 sequentially.
• p1 ~/ p2: matches p1, cuts backtrack, and then matches p2 sequentially.
• p./: matches p and then cuts backtrack.
• p1 | p2: matches p1, or matches p2.
• p.rep: repeats p matching many times.
• p.rep(min): repeats p matching n times (min <= n).
• p.rep(min, max): repeats p matching n times (min <= n <= max).
• p.count(n): repeats p matching n times.
• p.?: matches p, or succeeds without consuming any characters.
• p.named(name): names p for better error message.
• p.map(f), p.flatMap(f), p.filter(f): usual operators.

License

MIT License.

2020 (C) TSUYUSATO "MakeNowJust" Kitsune