Ruby If Nil Then 0

Ruby supports a rich set of operators as you d expect from a modern language.

Ruby if nil then 0. Most operators are actually method calls. The values false and nil are false and everything else are true. Then because conditional statements treat nil as false we can write. Remember also that a ruby method returns nil by default.

Railsの拡張 nil のいずれかでtrueを返す. The second form creates a copy of the array passed as a parameter the array is generated by calling to ary on the parameter. 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. 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.

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. In the first form if no arguments are sent the new array will be empty. There is a corresponding form of abbreviated assignment operator. Let s evaluate their usefulness and potential problems that they bring to the table.

Method in the object referred to by variable a is called with b as its argument. In ruby on rails what s the difference actually. Everything else in ruby is considered true in a boolean context. Some languages consider the number 0 as a false value but that s not the case in ruby.

Executes code if the conditional is true. If 0 is true then print 123. If the conditional is not true code specified in the else clause is executed. If 0 puts 123 end 123 this is saying.

And even those speaking ruby quite fluently don t usually know the tiny little details. Returns a new array. Notice ruby uses elsif not else if nor elif. For each operator plus.

Even 0 is true. I m new to ruby and i was surprised when i found out that all objects are true apart from nil and false. September 11 2010 4 minute read tags. For example a plus.

There are plenty of options available. B is interpreted as a plus b where the plus.