How to handle possibly null values in getProp? about immutableassign HOT 5 CLOSED

Maybe TS is smart enough to infer notnullability from this:
if(state.foo) state = iassign(state, g=>g.foo.bar, s => 1);
Otherwise ! might be used (or there is another syntax?).
if(state.foo) state = iassign(state, g=>g!.foo.bar, s => 1);

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IMHO I think that your "if" logic should go to "setter" function. Getter is just "semantical description of path", it is not real imperative code... hence no imperative "if".

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Hmm. That makes the setter bit awkward depending on the case. I think #15 would solve this nicely?

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Interesting use case, I don't think #15 (proxy) would work for your case. But feel free to try out that pull request, and let me know if it works.

Another solution I can think of is using nested iassign.

const newState = i(
    state,
    s => s.foo,
    (foo) => {
        return i(foo || {}, (f) => f.bar, () => 1);
    },
);

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Hi epeli,

Your use case should work now with 2.0.4 and following modification:

let newState = i(
    state,
    s => {
        const foo = s.foo;
        if (foo) {
            return foo.bar;
        }

        // must return the same value as the setProp() to prevent update.
        return 1;
    },
    () => 1,
    undefined,
    {
        ignoreIfNoChange: true,
    }
);

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