區塊 (block) 和範疇 (scope)

區塊

A block in Rust contains a sequence of expressions, enclosed by braces {}. Each block has a value and a type, which are those of the last expression of the block:

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If the last expression ends with ;, then the resulting value and type is ().

Speaker Notes

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  • 你可以藉由改變區塊中的最後一行來觀察區塊數值的變化。舉例來說,新增或刪除一個分號,或者使用 return