Matcher

Context-free language parsing library

Basic Usage

The code below shows basic usage of the Matcher libraries to generate an AST from a snippet of code.

string code = "1 + 3 + 5 + 7 * 2 * 4 * 6 + 9 + 11 + 13 * 8 * 10 * 12";
string definitionJson = File.ReadAllText("./ExpressionDefinition.json");
LanguageMatcherDefinition definition = JsonConvert.DeserializeObject<LanguageMatcherDefinition>(definitionJson);
LanguageMatcher matcher = DefinitionConverter.Convert(definition);
ILanguageMatchEngine matchEngine = MatcherEngineGenerator.GenerateEngine(matcher);
IMatchData matchData = matchEngine.Match(code).MatchData;

Here’s a breakdown of some of the classes used above:
LanguageMatcherDefinition - Model class to allow easy deserialization of the grammar from JSON, XML, etc. See Schema Details
LanguageMatcher - Internal form of the grammar used to generate a parser
MatcherEngineGenerator - Dynamic parser generator
ILanguageMatchEngine - Parser
IMatchData - Represents the Abstract Syntax Tree.

Sub-Libraries

Matcher.Interop.Model

Provides grammar model classes and a conversion utility to convert the models into a structure understood by the engine.

Patterns

Patterns are written using a syntax very similar to Regex, that supports the most popular operations, but also provides performance benefits.

Feature	Symbols	Compare To (Regex)	Example Usage	Example Match
Or					a	b	b
Grouping	( )	( )	a(b	c)	ab
Character Range	[ ]	[ ] (Note: Only for ranges)	[a-f]-[1-5]	c-2
Repeat Count	{ }	{ }	a{2} a{2, 4}	aa aaa
Any Character	.	.	a.e	are
Zero or More	*	*	a*b	b aaaab
One or More	+	+	a+b	aaab
Zero or One	?	?	a?b	ab b
Not	!	(?! )	a!.c	avc
Escape Character	\	\	a.e	a.e
New Line	\n	\n	a\nb	a… b
Carriage Return	\r	\r
Digit	\d	\d	a\d	a2
Letter	\l	\p{L}	a\l	ab
Tab	\t	\t	a\tb	a b
Whitespace	\s	\s	a\sb	a b
Word Character	\w	\w	a\w\wb	ae2b
Whole Word	` (prefix only) | \b \b | `var	%var% (If already at char index 1)
Case Insensitive	~ (prefix only)	(?i)	~size	SiZe

Matcher.Interop.Ebnf

Provides a utility to convert a grammar written in a form of BNF/EBNF to the internal representation of the grammar understood by the parser generator. There are many features that the parser generator supports that cannot be represented in BNF/EBNF, therefore using this is not recommended.

Matcher.CLI

Program for generating a parser that can be outputed as a class or assembly using the command line.

Usage:
  ./matchercli [<json definition file path>[ [<output directory>[ <output type>]]] [options]
	options:
	  --def		The json definition file path. Default: Read from stdin
	  --out		The directory to output generated file. Not applicable for 'stdout' output type. Default: Current directory
	  --type	Output type (i.e. class, assembly, stdout). Default: class