tonic + npm: gray-matter

const gm = require("gray-matter") const assert = require("assert"); const input = `--- title: test --- hello there`; const inputParsed = gm(input); const output = gm.stringify(inputParsed.content, inputParsed.data); console.log('input:'); console.log(input); console.log('output:'); console.log(output); assert(input === output);