JuliaParser.jl

A rewrite of Julia's parser in Julia
Author JuliaLang
Sub Category NLP
Category AI
Github
Popularity
91 Stars
Updated Last
3 Months Ago
Started In
March 2014

JuliaParser

Build Status

Note: This package is unmaintained and heavily bitrotted. It will not parse up to date Julia code correctly!

A pure Julia port of Julia's parser. It strives to be fully compatible with Julia's built-in parser.

Differences with Julia's built-in parser

  • BigInt and Int128 numbers are treated as literal values instead of expressions.
  • Literal negation is done as negated literals rather than using Expr(:-)
  • QuoteNodes are replaced with Expr(:quote).

Using JuliaParser as your primary parser

JuliaParser provides a script that will replace the built-in parser by itself. You may load it as follows:

julia -L ~/.julia/v0.5/JuliaParser/bin/repl.jl

TODO items

  • performance improvements
  • refactor number tokenization
  • refactor to make it more useful to use as a library (right now it is pretty monolithic)

Trying it out

julia> Pkg.clone("JuliaParser")

julia> import JuliaParser.Parser
julia> import JuliaParser.Lexer

julia> src = """
              function test(x::Int)
                  return x ^ 2
              end
              """
julia> ts = Lexer.TokenStream(src);

julia> Lexer.next_token(ts)
:function

julia> Lexer.next_token(ts)
:test

julia> Lexer.next_token(ts)
'('

julia> Lexer.next_token(ts)
:x

julia> Lexer.next_token(ts)
:(::)

julia> Lexer.next_token(ts)
:Int

julia> ast = Parser.parse(src);

julia> Meta.show_sexpr(ast)
(:function, (:call, :test, (:(::), :x, :Int)), (:block,
    (:line, 2, :none),
    (:return, (:call, :^, :x, 2))
  ))

julia> dump(ast)
Expr 
  head: Symbol function
  args: Array(Any,(2,))
    1: Expr 
      head: Symbol call
      args: Array(Any,(2,))
        1: Symbol test
        2: Expr 
          head: Symbol ::
          args: Array(Any,(2,))
          typ: Any
      typ: Any
    2: Expr 
      head: Symbol block
      args: Array(Any,(2,))
        1: Expr 
          head: Symbol line
          args: Array(Any,(2,))
          typ: Any
        2: Expr 
          head: Symbol return
          args: Array(Any,(1,))
          typ: Any
      typ: Any
  typ: Any