tagged-template-dsl-example.js

const λ = ({raw}, ...subs) => {
  const expr = raw
    .reduce((prev, next, n) => prev + `(___subs[${n - 1}])` + next)
    .replace(/#(\d+)/g, (_, n) => `(___args[${n}])`)

  const evaluate = new Function('___subs', '___args', `return (${expr});`)

  return (...args) => evaluate(subs, args)
}

/*

> λ`(#0 + #2) * #1`(4, 7, 2)
42

> [{x: 'foo'}, {x: true}, {x: 3}].map(λ`#0.x`)
["foo", true, 3]

> const field = 'x', n = 4
> [{x: 8}, {x: 3}, {x: 9}].map(λ`#0[${field}] * (#1 + ${n})`)
[32,15,54]

*/

can we make this safer by making it type-safe with typescript?