basic-lisp.js

function parseTokens (code) {
	return code
		.split(/([()]|"(?:\\.|[^"])*"|;[^\n]*|\s+)/)
		.filter(token => !/^;|^\s|^$/.test(token))
}

function parseArray (tokens) {
	const array = []
	if (tokens.shift() !== '(') {
		throw new Error(`Expected '('`)
	}
	while (true) {
		if (!tokens.length) {
			throw new Error(`Expected ')'`)
		}
		if (tokens[0] === '(') {
			array.push(parseArray(tokens))
		} else {
			const token = tokens.shift()
			if (token === ')') {
				break
			} else {
				array.push(token)
			}
		}
	}
	return array
}

function renderProgram (array) {
	return array
		.map(renderExpression)
		.join(';\n\n')
}

function renderExpression (element) {
	return Array.isArray(element)
		? renderCall(...element)
		: element
}

function renderCall (head, ...tail) {
	return `${renderExpression(head)}(${tail.map(renderExpression).join(', ')})`
}

const code = `
	(console.log "Hello world!")

	((console.log.bind console) "Hello world!")
`

const wrapped = `(${code})`
const tokens = parseTokens(wrapped)
const array = parseArray(tokens)
const program = renderProgram(array)

console.log(program)