Make value captured in recipe available in parent scope?

[tippfelher]

🙋‍♂ Question

I want to capture the value inside a recipe and have its value available after the Updater called the recipe. (see repro below)

Relevant code:

  function becomeOlder() {
    var captureAge = 0;
    updatePerson((draft) => {
      draft.age++;
      captureAge = draft.age;
      console.log("before", captureAge);
    });
    console.log("after", captureAge);
  }

Actual output example:

before 36
after 0

Wanted output example

before 36
after 36

Is that somehow possible?

Link to repro

Here is the corresponding playground.

Environment

We only accept questions against the latest Immer version.

• Immer version: 9.0.12
• useImmer version: 0.9.0
• Occurs with setUseProxies(true)
• Occurs with setUseProxies(false) (ES5 only)
• I ❤️ immerjs

[Michel Weststrate]

No it isn't, variables are fundamental feature of JavaScript which Immer can't interact with. Note that you could just have const captureAge =.... inside the draft to shadow the outer one.

[tippfelher]

Nvm, problem is gone and has nothing to do with immerjs but useImmer. I just implemented useBetterImmer which allows me to access the nextstate.