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TypeScript- assert type of keys in Object.entries forEach（1个答案）
昨天关门了。
以下内容的正确类型是什么：

type Composition = {
  foo: number;
  bar: number;
};

const total = 4;
const composition: Composition = { foo: 3, bar: 1 };

for (const [key, value] of Object.entries(composition)) {
  composition[key] = (value / total) * 100;
  // ^--- Element implicitly has an 'any' type because expression of type 'string' can't be used to index type 'Composition'.
  // ^--- No index signature with a parameter of type 'string' was found on type 'Composition'
}