Ruby Interview Questions

Ruby Interview Questions and Answers

Ruby is a dynamic programming language, basically, it is focused on the simplicity and productivity of code as well as it also supports more than one programming paradigm. Ruby contains different types of blended functions such as Perl, small talk, etc. Ruby provides the dynamic nature of a program which means it provides stability. Basically, it is used for web application development as well as other types of development we can use ruby.

Top 15 Ruby Interview Questions and Answers

Below are the top questions and answers of Ruby. These questions are helpful while giving mock tests or interviews.

Q1. How many types of library classes are present in Ruby?

Answer:

Normally we know ruby libraries contain different types of domains such as thread programming, data type, etc. Some of the libraries are Text processing, CGI programming, Network Programming, and GUI programming.

Q2. What are the data types present in Ruby?

Answer:

Same as other programming ruby also contains text, string, Arrays, Booleans, and numbers but apart from this it also has some different types such as Symbols, Hashes, etc.

Q3. Can you explain how can we create the object in Ruby?

Answer:

In ruby when we call a new method for the class at that time an object will be created and one more important thing it contains a unique type of method that is already predefined in the library.

Q4. What is the Ruby module?

Answer:

A collection of modules and methods is called a Ruby module. An instance method or a module method can make up a module method. Because they contain a collection of methods, class definitions, modules, and other modules, they are similar to classes. Like classes, they are defined. Modules are unable to be used to create objects or subclasses. There is no inheritance hierarchy for modules.

Basically, there are two purposes of the module as follows.

1. It uses the namespace

2. It allows sharing of the functionality between the different classes.

Q5. What is an array and can we create it in Ruby?

Answer:

Basically, arrays are nothing but ordered collections of objects and it stores the different values with different data types such as integer, number, hash, string as well as symbol. We know that array indexes always start with 0 as same as other programming languages and end with -1.

Q6. What are the naming conventions used in Ruby?

Answer:

Variables: It is used to declare the variable and it contains all letters with the lower and upper case as well as it also allows us to use the underscore as a separate.
Class and Module: This is used for the mixed-case and it does not allow using underscore. In this naming convention class or module name always starts with the upper letter.
Database Table: Database table name contains lowercase letters and here we can use an underscore between the letters and all names must be in plural structure.
Model: Model names use the mixed case and it is always a singular case.
Controller: In the controller, naming convention class name is used in a plural structure.

Q7. What are hashes in Ruby?

Answer:

Ruby hash is nothing but a combination of unique keys and their values are the same as an array. Still, one major difference is that we know an array uses an integer value as an index but hash uses any object type for index. The method will return the null when we try to use a hash key for access.

Q8. What are iterators and their types?

Answer:

Basically, iterators are one of the concepts used in object-oriented programming, iterators are nothing but doing tasks many times, for example, we can consider a loop. It is a very simple example of an iterator and it all returns the data from the collection.

Basically, there are five types of iterators in ruby as follows.

Each iterator
Times iterator
Up-to and down-to iterator
Step iterator
Each line iterator

Q9. Explain how to open a file with syntax in ruby.

Answer:

In the ruby programming language we have different methods to create files for reading, writing, or sometime for both.

Basically, there are two different methods used to open files in ruby as follows.

File.new method: With the help of this method we can create a new file for reading or writing purposes or both.
File.open method: With the help of this method we can create a new file object and this object will be assigned to the file.

Syntax:

fi = File.new("specified file name") or

Q10. What is an exception in ruby?

Answer:

Normally ruby exceptions are used for the instance of a class. Exceptional behavior is displayed by the Ruby program whenever something goes wrong. Ruby programs always end when an exception is thrown.

Q11. What is the use of ensure statements in Ruby?

Answer:

Basically, ensure clause is used to determine the process for the end of the code. Ensure clause of whether an exception is raised, the ensure block continues to run. It always takes effect when the block ends, and it is placed after the last rescue clause. Ensure clause of whether an exception occurs, an exception is rescued, or code is terminated by an uncaught exception, the ensure block will run.

Q12. What is the difference between calling super() and calling super in Ruby?

Answer:

When super is called, the parent method is called with the same arguments as the child method. Therefore, if the arguments passed to the child method don’t match what the parent expects, an error will occur.

As would be expected, calling super() calls the parent method without providing any arguments. Being clear in your code is always a good thing.

Q13. How can we call private methods outside the class with the help of an object?

Answer:

Yes, we can do it with the help of the send method as follows.

class rubysample
            private
                        def method
                                    P "required string"
                        end
end

Q14. What is the difference between the Symbol and String?

Answer:

Basically, the structure of both is the same but the difference is only behaviors that are totally different. Basically, symbols belong to immutable objects and a String is a mutable object.

Q15. What is Mixin Used?

Answer:

It is used when we want to implement multiple inheritances by using a mixin module.

Conclusion

From this article, we are able to understand the Ruby Interview Question. It provides the basic idea about the mid-level and higher-level concepts of ruby programming. Ruby Interview Question is a key point for every interview or we can say that every technology.