@thi.ng/args/coerce.js

Declarative, functional CLI argument/options parser, app framework, arg value coercions, multi/sub-commands, usage generation, error handling etc.

import { isHex } from "@thi.ng/checks/is-hex";
import { isNumericFloat, isNumericInt } from "@thi.ng/checks/is-numeric";
import { illegalArgs } from "@thi.ng/errors/illegal-arguments";
import { Tuple } from "./api.js";
const coerceString = (x) => x;
const coerceFloat = (x) => isNumericFloat(x) ? parseFloat(x) : illegalArgs(`not a numeric value: ${x}`);
const coerceHexInt = (x) => isHex(x) ? parseInt(x, 16) : illegalArgs(`not a hex value: ${x}`);
const coerceInt = (x) => isNumericInt(x) ? parseInt(x) : illegalArgs(`not an integer: ${x}`);
const coerceJson = (x) => JSON.parse(x);
const coerceOneOf = (values) => (x) => values.includes(x) ? x : illegalArgs(`invalid option: ${x}`);
function coerceKV(delim = "=", strict = false, multi = false) {
  return (pairs) => pairs.reduce((acc, x) => {
    const idx = x.indexOf(delim);
    strict && idx < 1 && illegalArgs(
      `got '${x}', but expected a 'key${delim}value' pair`
    );
    if (idx > 0) {
      const id = x.substring(0, idx);
      const val = x.substring(idx + 1);
      if (multi) {
        acc[id] ? acc[id].push(val) : acc[id] = [val];
      } else {
        acc[id] = val;
      }
    } else {
      acc[x] = multi ? ["true"] : "true";
    }
    return acc;
  }, {});
}
const coerceTuple = (coerce, size, delim = ",") => (src) => {
  const parts = src.split(delim);
  parts.length !== size && illegalArgs(`got '${src}', but expected a tuple of ${size} values`);
  return new Tuple(parts.map(coerce));
};
export {
  coerceFloat,
  coerceHexInt,
  coerceInt,
  coerceJson,
  coerceKV,
  coerceOneOf,
  coerceString,
  coerceTuple
};