if 表達式

你可以像在其他語言中使用 if 陳述式那樣地使用 if 表達式：

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此外，你也可以將 if 當作表達式使用。每個區塊中的最後一行式子將成為 if 表達式的賦值：

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Speaker Notes

 This slide should take about 4 minutes.

Because if is an expression and must have a particular type, both of its branch blocks must have the same type. Show what happens if you add ; after "small" in the second example.

在運算式中使用 if 時，運算式須有 ;，才能與下一個陳述式分隔。移除 println! 前的 ; 即可查看編譯器錯誤。