https://github.com/edadma/indentation-lexical

A lexical component that can be used to build a parser for a language that has "indentation syntax" or "off-side rule syntax"
https://github.com/edadma/indentation-lexical

Last synced: 14 days ago
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A lexical component that can be used to build a parser for a language that has "indentation syntax" or "off-side rule syntax"

• Host: GitHub
• URL: https://github.com/edadma/indentation-lexical
• Owner: edadma
• License: isc
• Created: 2014-05-02T01:47:07.000Z (almost 11 years ago)
• Default Branch: master
• Last Pushed: 2020-04-06T20:59:55.000Z (almost 5 years ago)
• Last Synced: 2024-11-19T10:12:50.745Z (3 months ago)
• Language: Scala
• Size: 40 KB
• Stars: 1
• Watchers: 1
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

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README

        
# Indentation Lexical

This is a lexical component that can be used instead of `StdLexical` to build a parser for a language that has "indentation syntax" or "off-side rule syntax".

Refer to `ToyParser.scala` in the project as an example of how to add this to your parser.  There is nothing special about the "toy" language that has been included: it doesn't even have loop constructs or a way to define functions. It was just created to demonstrate how to use `class IndentationLexical`.

In `ToyParser.scala`, the main source lines of interest are

	def parse( r: Reader[Char] ) = phrase( source )( lexical.read(r) )

	import lexical.{Newline, Indent, Dedent}

Although `IndentationLexical` extends `StdLexical`, you do not create an instance of `Scanner` as you would normally.  `IndentationLexical` has it's own scanner.