Unary Plus(+) and Minus(-) Operators in Ruby

Redefinition of Unary + and - Operators

As the name in both the unary and binary versions of + and - operators are the same, it can create conflict while redefining the operator in a method. The unary version's method has a suffix of @ for this ambiguity.

The names of these unary operators in methods are -@ and +@. Below is an example of redefining the Unary + and - operator in a method.

Example

str = "This is Coding Ninjas"

#redefining the unary - operator
def str.-@
    downcase
end

#redefining the unary + operator
def str.+@
    upcase
end

p str
p -str
p +str

You can also try this code with Online Ruby Compiler

Run Code

Output

"This is Coding Ninjas"
"this is coding ninjas"
"THIS IS CODING NINJAS"

Explanation

In the above example, we have defined the unary - operator(using the -@ method) to translate the receiving object(String) to lower case, and we have defined the unary + operator(using the +@ method) to translate the receiving object(String) to upper case. The output is as expected.

Read about Bitwise Operators in C here.

Frequently Asked Questions

What are the different Arithmetic operators present in Ruby?

The different arithmetic operators present in Ruby are the followings:

• Addition(+)
• Subtraction(-)
• Multiplication(*)
• Division(/)
• Modulus(%)
• Exponent(**)
   

What is the ternary operator in Ruby?

The ternary operator in Ruby is a conditional expression that first evaluates an expression for true or false. Based on the evaluation's result, It executes one of the two given statements. 

The syntax is as follows, (Condition)? (Statement1) : (Statement2).

If the condition is true, then statement1 will execute. Otherwise, statement2 will execute.
 

What do you mean by the parallel assignment in Ruby?

The parallel assignment in Ruby is a method of assigning multiple variables with a single line of code.

For example,

A = 1
B = 2
C = 3
# is same as
A , B , C = 1 , 2 , 3

You can also try this code with Online Ruby Compiler

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We can also use the parallel assignment in swapping two variables as shown below,

A , B = B , A

What are the range operators in Ruby?

The range operators in Ruby are used to create a sequence of successive values. The range consists of a start value and an end value, and in between these two values, we have an operator("..", "...").

The ".."(two-dot form)" creates an inclusive range, whereas "..." (three-dot form) creates a range that excludes the end value.

Like,

1..5 contains the sequence (1 , 2 , 3 , 4 , 5)
1...5 contains the sequence (1 , 2, 3, 4)

Conclusion

This article extensively discussed Unary Plus(+) and Minus(-) Operators in Ruby.

We started this article with a basic introduction. Then we discussed the following points:

• What are the Unary Operators in Ruby
• Unary Minus(-) Operator
• Unary Plus(+) Operator
• Redefinition of unary + and - Operators
   

We hope that this blog gives you some ideas regarding Unary Plus(+) and Minus(-) Operators in Ruby. If you would like to learn more, follow our articles on Bitwise NOT(~), AND(&), OR(|) and XOR(^) Operations in Ruby, 8 Reasons Why Ruby Should be Your First Language, Ruby and Ruby On Rails: How do they differ?, Boolean in Ruby and Nonoperators in Ruby. Explore our practice platform Coding Ninjas Studio to practice top problems, attempt mock tests, read interview experiences, interview bundle, follow guided paths for placement preparations and much more.!

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