map的遍历赋值：实践出真知（修正作者的错误理解）

The issue body only gives a title and an image link, with no file, test, or reproduction details. Start by locating the documentation chapter about map iteration/assignment where this statement appears (likely in markdown content), since no file path is provided. Read surrounding sections for expected wording, then update the text to correct the explained behavior. Done when the docs section explicitly and consistently reflects the right map traversal assignment semantics.

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