However in functional languages like Haskell and Clojure, if is an expression and it must return a value. So it must be succeeded with an else. However there are still cases where you may not need an else section. Clojure, for such cases, has a when macro which wraps if - else to return nil in the else section and avoid writing it.
One reason very old languages use this distinct syntax instead of "else if" is that the "else if" introduces a grammar ambiguity. Old parser generators were hard to teach about what to do for ambiguities, so we avoided them.
The statements in the else block are executed if execution falls off the bottom of the try - if there was no exception. Honestly, I've never found a need. However, Handling Exceptions notes: The use of the else clause is better than adding additional code to the try clause because it avoids accidentally catching an exception that wasn’t raised by the code being protected by the try ...
I am trying to discern the difference between: if else and else if How do you use these? And when do you use them and when not?
5 Как такового оператора else if нет, это лишь использование ещё одного if в ветке else другого if. Но разница между ними есть.
IF, ELSE IF, ELSE ou IF IF IF. Quando usar, qual a diferença? Perguntada 11 anos, 5 meses atrás Modified 4 anos, 11 meses atrás Vista 87mil vezes
IF, ELSE IF, ELSE ou IF IF IF. Quando usar, qual a diferença?
Queria saber qual a diferença entre else e elseif em PHP, e quando devo usar um ou outro.