Json5 parser for luajit

This crate provides json5 deserialization for luajit.

Inspired and adapted from json5-rs

Also, if you haven't already, add ';?.dylib' to your package.cpath so it will be recognized by the interpreter.

Usage

You can simply require the module in your scripts and parse a string using the parse method:

local parse = require'json5'.parse
local data = [[
{
    / This is a comment /
    ecma_identifier: 'works like a charm',
    "string keys": [1,2,3], // trailing comma
}
]]
local parsed_data = parse(data)

Use with neovim

You must have cargo installed and in your $PATH

Using packer.nvim:

use {
    'Joakker/lua-json5',
    -- if you're on windows
    -- run = 'powershell ./install.ps1'
    run = './install.sh'
}

Using lazy.nvim

{ 
    'Joakker/lua-json5',
    build = './install.sh',
}

Lua 5.4

You can also build the library for lua 5.4 using the following command:

cargo build --no-default-features --features lua54 --release

Performance

Tested on neovim using the following script:

local data = [[ {"hello":"world"} ]]
local json5 = require('json5').parse
local jsondecode = vim.fn.jsondecode
local timejson5, timejson_decode = 0, 0
local aux
for _ = 1, 1000 do     aux = os.clock()     json5(data)     timejson5 = timejson5 + (os.clock() - aux) end
for _ = 1, 1000 do     aux = os.clock()     json_decode(data)     timejsondecode = timejsondecode + (os.clock() - aux) end
print(('json5:        %.3fms'):format(time_json5)) print(('jsondecode:  %.3fms'):format(timejson_decode))

On average:

json5:        0.023ms json_decode:  0.010ms

So, why should I use this instead of the builtin `json_decode`?

If performance is your concern, I think you're better off using the builtin function json_decode. The advantage this package has over regular json, however, is that you get json5 features, such as comments, trailing commas and more flexible string literals.

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