if
式
Rust の if
式 は、他の言語における if
文と全く同じように使えます。
さらに、if
を式としても用いることができます。それぞれのブロックにある最後の式が、if
式の値となります。
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.
An if
expression should be used in the same way as the other expressions. For example, when it is used in a let
statement, the statement must be terminated with a ;
as well. Remove the ;
before println!
to see the compiler error.