Ruby Check Nil Or Empty String

For example nil and are blank.

Ruby check nil or empty string.

Well nil is a special ruby object used to represent an empty or default value. An empty string is one that is not nil it is a string right and has no bytes nothing. Now let s cover a much more specific way of representing a lack of data and that is emptiness. Is a string class method in ruby which is used to check whether the string length is zero or not.

True true false false nil false 0 true abc true. Method inside the string class. You need to check the documentation for each case. That means that an empty string is not nil and an empty array is not nil.

Is a method some objects respond to. An object is blank if it s false empty or a whitespace string. Returned nil or a string or a number something different than true or false. Returns nil if the instance was nil and nonzero.

Rails adds the method blank. It s also a falsy value meaning that it behaves like false when used in a conditional statement. Method is analogous to the following. This is useful in case empty.

Anything can potentially be nil and every object can answer to the nil method. Return length 0 end so you can safely use. You can think of nil as the most general way of representing absence in ruby. If the number was 0.

For example and empty array is one that is not nil it is an array right and has no elements. Class string def present. Any string length 0 anyway using that code inside an else if is a bit verbose i would encourage you to define the present. That way the returned value is always converted to a boolean value.

From ruby 2 3 0 onward you can combine the safe navigation operator with numeric nonzero. The source of the empty. Will only return true if the object itself is nil.