jdh30

type Json =
  | Null
  | Bool of bool
  | Number of float
  | String of string
  | Array of Json list
  | Object of (string * Json) list

type Bracket = Open | Close

yelouafi

In this tutorial we're going to build a set of parser combinators.

What is a parser combinator?

We'll answer the above question in 2 steps.

1. What is a parser?
2. and, what is a parser combinator?

So first question: What is parser?

jdh30

    > let alpha = set['a'..'z'] + set['A'..'Z'];;

    > let num = set['0'..'9'];;

    > let alphanum = alpha + num;;

    > let (|Char|_|) alphabet = function
        | c::cs when Set.contains c alphabet -> Some(c, cs)
        | _ -> None;;

jdh30

    {
    open Parse
    open Lexing
    let ident = function
      | "let" -> LET
      | "rec" -> REC
      | "in" -> IN
      | "fun" -> FUN
      | "if" -> IF
      | "then" -> THEN

jdh30

    > let pInt : Parser<_, unit> = puint32 |>> int .>> spaces;;

    > let str s = pstring s >>. spaces;;

    > let keywords =
        "if then else let rec in fun".Split ' '
        |> set;;

    > let pIdent : Parser<_, unit> =

amitchhajer

git ls-files -z | xargs -0n1 git blame -w | perl -n -e '/^.*\((.*?)\s*[\d]{4}/; print $1,"\n"' | sort -f | uniq -c | sort -n