oelin / naoki

A parser generator for C.

Naoki

A parser generator for C. WIP.

Installation

npm i -g naoki

Usage

naoki path/to/grammar.txt

Example

Define a grammar.

# grammar.txt

Proposition      > "[A-Z]"
UnaryOperator    > "¬"
BinaryOperator   > "^"
                 | "v"
                 | ">"
UnaryExpression  > UnaryOperator Expression
BinaryExpression > "(" Expression BinaryOperator Expression ")"
Expression       > Proposition
                 | UnaryExpression
                 | BinaryExpression

Compile it.

$ naoki grammar.txt

Congratulations, you now have a parser 🥳.

// grammar.h

...

// Variables.

Variable(Proposition);
Variable(UnaryOperator);
Variable(BinaryOperator);
Variable(UnaryExpression);
Variable(BinaryExpression);
Variable(Expression);

// Production rules.

Production(Proposition, Match("[A-Z"));
Production(UnaryOperator, Match("¬"));

Production(
  BinaryOperator, 
  Or(
    Match("\\^"),
    Or(
      Match("v"),
      Match(">")
    )
  )
);

Production(
  UnaryExpression, 
  And(
    UnaryOperator,
    Expression
  )
);

Production(
  BinaryExpression, 
  And(
    Match("\\("),
    And(
      Expression,
      And(
        BinaryOperator,
        And(
          Expression,
          Match("\\)")
        )
      )
    )
  )
);

Production(
  Expression, 
  Or(
    Proposition,
    Or(
      UnaryExpression,
      BinaryExpression
    )
  )
);

Try it on some strings.

#include "grammar.h"

parse(Expression, "hello world"); // Returns `NULL` as "hello world" is not an `Expression`.

parse(Expression, "((AvB)^C)");   // Returns a parse tree.