A first-class representation of an NLD-based grammar.

Combine a list of Grammar values into a single Seq, flattening any nested Seq nodes.

import Nld.TokenType exposing (TokenType(..))


seq [ Literal "hello", Literal "world" ]
--> Seq [ Literal "hello", Literal "world" ]


seq [ Literal "a", Seq [ Literal "b", Literal "c" ] ]
--> Seq [ Literal "a", Literal "b", Literal "c" ]

Combine a list of Grammar values into a single Choice, flattening any nested Choice nodes.

import Nld.TokenType exposing (TokenType(..))


choice [ Literal "yes", Literal "no" ]
--> Choice [ Literal "yes", Literal "no" ]


choice [ Literal "a", Choice [ Literal "b", Literal "c" ] ]
--> Choice [ Literal "a", Literal "b", Literal "c" ]

Encode a Grammar as a JSON value.

import Json.Encode as Encode
import Nld.TokenType exposing (TokenType(..))


encode (Token NatToken)
--> Encode.object [ ( "tag", Encode.string "token" ), ( "value", Encode.object [ ( "tag", Encode.string "nat" ) ] ) ]

Decode a Grammar from JSON.

import Json.Decode as Decode


Decode.decodeString decoder """{"tag":"anyToken"}"""
--> Ok AnyToken