st/set

Overwrite a mutable variable with a new value

// 1. make an app
const app = mvfm(prelude, st);

// 2. make a program
const prog = app({ x: "number" }, ($) => {
  const cell = $.let(0);
  cell.set($.mul($.input.x, 2));
  return cell.get();
});

// 3. run
await fold(
  defaults(app),
  injectInput(prog, { x: 21 })
);

// 1. make an app
const app = mvfm(prelude, st);

// 2. make a program
const prog = app({ x: "number" }, ($) => {
  const cell = $.let(0);
  cell.set($.mul($.input.x, 2));
  return cell.get();
});

// 3. run
await fold(
  defaults(app),
  injectInput(prog, { x: 21 })
);

// 1. make an app
const app = mvfm(prelude, st);

// 2. make a program
const prog = app({ x: "number" }, ($) => {
  const cell = $.let(0);
  cell.set($.mul($.input.x, 2));
  return cell.get();
});

// 3. run
await fold(
  defaults(app),
  injectInput(prog, { x: 21 })
);

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