私はJava→Objective-Cの順で学んだプログラマなのだが、 Objective-Cにおいて、以下のように空文字列チェックをしていた。 #define IS_EMPTY(s) ((s == nil) || ([s length] == 0)) NSString *emptyString = @""; NSString *nilString = nil; NSString *someString = @"foo"; // nilまたは空文字列でないかチェックする NSLog(@"%@", !IS_EMPTY(emptyString) ? @"YES" : @"NO"); NSLog(@"%@", !IS_EMPTY(nilString) ? @"YES" : @"NO"); NSLog(@"%@", !IS_EMPTY(someString) ? @"YES" : @"NO"); し
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