How to append a String in Ruby?

Ruby | Append a string: Here, we are going to learn how to append a string in Ruby programming language?
Submitted by Hrithik Chandra Prasad, on May 07, 2020

There are multiple ways to do the required but we will study about three of them.

Method 1: With the help of predefined method concat()

The concat() is a predefined method for String class in Ruby's library. This method is used for carrying out concatenation between two String instances.

Syntax:

    String1.concat(String2)

Variables used:

Str1, Str2 and Str3: The three are the instances of String class. Str1 is the String class object which is going to be appended.

Program:

=begin
  Ruby program to append a String with the 
  help of concat() method.
=end

Str1 = "Includehelp"
Str2 = ".com"

puts "Str1 is #{Str1}"
puts "Str2 is #{Str2}"
Str3 = Str1.concat(Str2)

puts "The appended String object is #{Str3}"

Output

Str1 is Includehelp
Str2 is .com
The appended String object is Includehelp.com

Explanation:

In the above code, you can observe that we have three strings namely Str1, Str2, and Str3. We are appending Str2 into Str1 with the help of String.concat method. We are storing the appended String in Str3 container.

Method 2: With the help of << operator

The << is a predefined method/operator for String class in Ruby's library. This method is used for carrying out concatenation between two String instances.

Syntax:

    String1 << String2

Variables used:

Str1, Str2, and Str3: The three are the instances of String class. Str1 is the String class object which is going to be appended.

Program:

=begin
  Ruby program to append a String with the 
  help of << operator.
=end

Str1 = "Includehelp"
Str2 = ".com"

Str3 = Str1<<Str2

puts "The appended String object is #{Str3}"

Output

    The appended String object is Includehelp.com

Explanation:

In the above code, you can observe that we have three strings namely Str1, Str2, and Str3. We are appending Str2 into Str1 with the help of << operator. We are storing the appended String in Str3 container.

Method 3: With the help of + operator

The + is a predefined method/operator for String class in Ruby's library. This method is used to carry out addition between two String instances. Adding can be considered as appending as well.

Syntax:

    String3 = String1 + String2

This way is less efficient in comparison with other two because you need to have a temporary storage to store the resultant String which is not the case of concat() and << method.

Variables used:

Str1, Str2 and Str3: The three are the instances of String class. Str1 is the String class object which is going to be appended.

Program:

=begin
  Ruby program to append a String with 
  the help of + operator.
=end

Str1 = "Includehelp"
Str2 = ".com"

Str3 = Str1 + Str2

puts "The appended String object is #{Str3}"

Output

The appended String object is Includehelp.com