Ruby If Nil Then 0

B is interpreted as a plus b where the plus.

Ruby if nil then 0. Memoirs of a software team leader read more. And even those speaking ruby quite fluently don t usually know the tiny little details. There is a corresponding form of abbreviated assignment operator. Railsの拡張 nil のいずれかでtrueを返す.

Method in the object referred to by variable a is called with b as its argument. September 11 2010 4 minute read tags. Even 0 is true. For example a plus.

Everything else in ruby is considered true in a boolean context. In ruby on rails what s the difference actually. Let s evaluate their usefulness and potential problems that they bring to the table. In the first form if no arguments are sent the new array will be empty.

Some languages consider the number 0 as a false value but that s not the case in ruby. Most operators are actually method calls. An if expression s conditional is separated from code by the reserved word then a newline or a semicolon. Then because conditional statements treat nil as false we can write.

If you ve ever coded in php then you ve certainly had to deal with null and the same goes for c java and pretty much every mainstream modern programming language. If 0 is true then print 123. Notice ruby uses elsif not else if nor elif. For each operator plus.

If the conditional is not true code specified in the else clause is executed. When a size and an optional default are sent an array is created with size copies of default take notice that all elements will reference the same object default. Ruby supports a rich set of operators as you d expect from a modern language. The values false and nil are false and everything else are true.

Executes code if the conditional is true. For many beginning rubyists especially those having experience in other programming languages such as java or c checking whether variable is nil may seem a little bit confusing. Ruby of course isn t the only language that needs the concept of nothing far from it. Remember also that a ruby method returns nil by default.

The second form creates a copy of the array passed as a parameter the array is generated by calling to ary on the parameter. There are plenty of options available.