@jplorg/jpl/src/builtins/funcToUpperCase.js

JPL interpreter

import { JPLTypeError } from '../library';

async function builtin(runtime, signal, next, input) {
  const t = runtime.type(input);

  switch (t) {
    case 'string':
      return next(await runtime.alterValue(input, (value) => value.toUpperCase()));

    default:
  }

  throw new JPLTypeError(
    '%s (%*<100v) cannot be converted to upper case',
    t,
    runtime.unwrapValue(input),
  );
}

export default builtin;