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Ruby switch case or.
The components of a case statement in ruby.
Ruby case statement syntax case expression when expression expression then code.
Whenever you need to use some if elsif statements you could consider using a ruby case statement instead.
In this post you will learn a few different use cases and how it all really works under the hood.
In most computer languages the case or conditional also known as switch statement compares the value of a variable with that of several constants or literals and executes the first path with a matching case in ruby it s a bit more flexible and powerful.
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In computer programming languages a switch statement is a type of selection control mechanism used to allow the value of a variable or expression to change the control flow of program execution via search and map.
Ruby case statement last updated.
1 is a fixnum hello is a string 2 is a 1 3 in the range of 比较让人产生误解的 大概就是1 1也为true 所以理解起来 也不纯碎是is a关系.
It provides an easy way to forward execution to different parts of code based on the value of the expression.
Ruby exceptions the execution and the exception always go together.
Switch statements function somewhat similarly to the if statement used in programming languages like c c c visual basic net java and exists in most high level imperative.
The case statement is a multiway branch statement just like a switch statement in other languages.
If 表达式用于条件执行 值 false 和 nil 为假 其他值都为真 请注意 ruby 使用 elsif 不是使用 else if 和 elif 如果 conditional 为真 则执行 code 如果 conditional 不为真 则执行 else 子句中指定的 code.
The expression specified by the when clause is evaluated as the left operand.