What is the reason for requiring that the value type in a map must be uniform?

When using TypeScript, I expect the map type to be either a number or string, but unfortunately, an error is being reported.

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const map: Map<string, string | number> = new Map([
    [
        '1',
        '1',
    ],
    [
        '2',
        1,
    ],
]);

error: No overload matches this call.

Answer №1

Using type declaration during initialization is effective:

const myMap = new Map<string, string | number>([
    [
        'apple',
        'red',
    ],
    [
        'banana',
        5,
    ],
]);

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