Is Scala interpreted or compiled?

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Interpretation and compilation are the most techniques used to express the Programming languages. Most programming languages are interpreted. Scala usually has an illusion of an interpreted language, but it is a compiled language. Arguably, Scala can both be interpreted and compiled.

Everything you type gets compiled to the byte code, and then it runs within the JVM.Scala possesses much different from other languages which are interpreted.

Both the Scala compiler and interpreter can execute the Scala codes differently depending on the technique chosen.

Scala compiler compiles your Scala code into Java byte code executed by Scala command; thus, Scala runs your compiled Scala code.

Though the Scala compiler tends to be slow to startup, the need to ignite speed is paramount. To increase this speed of compilation, Scala has a daemon that keeps running, thus faster operations. The slowness of Scala has contributed some things, which include;

  • Implicit resolution. Implicit resolution bubbles up over every parent scope in the declaration; thus, the search time becomes every massive in particular if you reference the same implicit variable many times, and it’s declared in some library down your dependency chain.
  • Use of a massive number of anonymous classes, i.e., lambdas, blocks, unknown function. For instance, if you are using standard HD instead of an SSD and have many unspecified levels, Scala has to generate a Java class for each lambda declaration, quickly adding up.
  • Macros. This added more compile time. Lots of analysis are needed in this area; thus, its heavy uses in the C++ program add s to the compile time.

Scala interpreter runs your Scala code directly as it is without the need for compiling it.

As an interpreter, Scala has numerous features like;

  • Type Inference 
  • Singleton Object
  • Immutability
  • Lazy Evaluation
  • Case Classes and Pattern Matching 
  • ImpliString Interpolation
Is Scala interpreted or compiled
Is Scala interpreted or compiled

Why was Scala created?

Have you ever questioned yourself? What were the main objectives for the building of Scala?

Before something is brought to life, some purposes are set so as it may accomplish. By so doing, then it is bringing relevancy for its creation.

Scala was designed to show the possibility and workability of the fusion of functional and object-oriented programming. It is purported that there were some milestones concerning Scala language dissemination because Scala has formed high-speed and essential projects, and companies adopted it quickly.

Click here if programming in Scala is your thing.

In its introduction, Scala developed a new approach that could take advantage of all of the existing Java code and allow new code to be written most productively and elegantly. Java had so many issues that its viability in the future was being questioned.

Java being a victim of its success, there was the need to support the increasingly significant investments in Java programs; thus, it was basically alright to introduce Scala.

Scala was also created to solve the interoperability with Java, which guarantees that you have libraries for anything and do not need to reinvent it. In Scala, developing on JVM and deploying on it is much easier. Scala is a platform that goes through years of optimization.

Scala stands out to be a very appealing and promising choice to developers looking to balance pure codes and write solid code quickly by building upon existing solutions and libraries when available.

Scala was meant to be fashionable since it was created based on being an all-purpose programming language that it has revealed. Its code is concise yet maintainable. It is bytecode compatible with Java and can use virtually all Java libraries and tools.

Scala encourages switching from mutable data structures to immutable ones and from standard methods to pure functions, thus reducing issues rooted in unintentional side effects common large codebases, which means that your code will be safer on the ouster, more stable, and easier to understand.

Scala’s short, expressive syntax avoids unnecessary punctuation and condenses map, filter, and reduce operations to simple one-liners. Never an expressive syntax is seen in other compiled languages.

Scala guarantees your code to be strongly typed and supports both multiple inheritances and mixin features. These mixin features allow you to write shortcode (them, ruby, python) ideal for engineers working in startup environments to get products out and enable engineers to write high-performance applications.

Scala imprints new ways on you to view the concepts of data mutability, higher-order functions, sophisticated type systems, etc.

Generally, Scala was created to solve most of the inconveniences experienced using other programming languages. But it also stands out on its spheres to be a top-notch programming language.

What is Scala used for?

Depending on your perspectives, Scala has so many uses that one cannot imagine. Being a foundational programming language used for functional and robust static systems, Scala has dispersed its usefulness widely.

Scala has so much to offer.  Click here to start learning more.

It never has primitive data since it is considered a powerful static type language and can interoperate with the existing Java code and libraries. Being object-oriented enables it to run on the JVM.

Below is a list of top uses of Scala;

  • A multi-paradigm language

Scala supports object-oriented programming, and functional programming is good to learn since it builds imperative, logical, practical, and OOP skills through its Learning. Hence exploration of both sides of functional and OOP together is possible.

Scala allows you to define different types associated with both data attributes and behavioural attributes. Nevertheless, Scala functions are considered first-class, enabling you to pass values and support anonymous functions.

All these contribute to the elegancy of Scala and thus increasing its popularity in the market.

  • Scala can be used in amalgamation with Java.

Scala can run on the Java Virtual Machine (JVM), thus proving to be one of the best options due to its interoperability feature.

Scala developers will be able to use all Java libraries directly from Scala code, and beneficial to Java developers to leverage their skills in Scala easily. 

It is possible to call Scala code from Java, and the user can quickly write any part of a programing Scala and rest in Java. This feature generally enables a user to write code in Java and Scala and work together with both languages.

  • Pattern built-in language

To create innovations in programming languages research to mainstream languages like Java, Scala has some of the best practices and patterns built-in language. For example, variables are immutable and can be easily overloaded in Java.

Additionally, it offers to adopt new languages like Python, Ruby, etc., to implement functional programming.

  • Statically Typed Language

This helps programmers write proper code and debug the code easily since it can avoid mistakes. It also provides a compiler that uses type reference to a full extent, and it also provides type inference for variables and functions. Scala uses the best of both static and dynamic languages.

  • Growing Frameworks

Many Scala applications provide various libraries and can be used to build many frameworks, thus the great urge by many companies to work ahead to make Scala a mainstream language.

Like Akka, which is concurrent and established like a toolkit and a runtime for building a highly concurrent, distributed, and fault-tolerant system, these frameworks also provide event-driven JVM applications.

  • Precise Syntax

Scala has an exact syntax, thus more readable and concise at the same time.

The scala compiler known as Scala can generate and work for a better code like String (), equals (), etc.

  • Creating a Community

There is a significant transition to the Scala language even for those who already relevant to other languages. This because many libraries and frameworks are being built on the application of Scala.

The community is ever-growing since Scala is also dynamic, and many IDEs are being built, which support Scala and much better support Eclipse and IntelliJ.

v Indeed Scala has a varied range of uses once you know of it. Learning Scala will surely increase your value as a developer in the market. You will be able to develop new frameworks and use the dynamic feature of this language.

Due to Scala’s current trending at large all over the world, you will be able to reach new heights in your career.

Scala Programming Language

In this section ,you will understand how Scala came into play (history) ,the platforms, examples , Features as a language ,concurrency ,cluster computing ,testing ,versions ,adoption ,criticism ,etc.


The design of Scala started in 2001 at EPFL in Lausanne, Switzerland, by Martin Odersky. It followed on from work on Funnel, a programming language combining functional programming and Petri nets. Ordesky formally worked on Generic Java and Javac, Sun’s Java compiler.

Scala was released publicly in early 2004 after an internal release in late 2003 in the Java platform. In March 2006, a second version was enrolled.

In early 2011, the Scala team won a five-year research grant from the European Research Council. In the same year, Orders and collaborators launched Typesafe Inc., Later renamed “Lightbend Inc.” to provide commercial support, training, and services for Scala.

Platforms and license

Scala runs on the Java platform (Java virtual machine), and it is much compatible with the existing Java programs.

Since Android applications are typically written in Java and translated from Java byte code into Dalvik bytecode when packaged, Scala’s Java compatibility makes it well-suited to Android development, more so where a functional approach is preferred.

The reference Scala software distribution, including compiler and libraries, is released under the Apache license.


Here we can look at some of the features Scala uphold about Java.

Scala has the same compiling model as Java and C#, namely separate compiling and dynamic class loading so that Scala code can call Java libraries.

Scala generates byte code that is nearly identical to that caused by the Java code, even though Scala code can be decompiled to readable Java code, except for certain constructor operations.

Scala has a broad scope of features than Java and has fundamental differences in its underlying expressions and types, making the language theoretically cleaner and eliminating several corner cases in Java.

Scala has a good deal of syntactic flexibility compared with Java. For example, semicolons are unnecessary; instead, lines are automatically joined if they begin or end with a token that cannot come in this position.


Scala’s standard library includes support for the actor model, in addition to the traditional Java concurrency APIs.

Lightning Inc. provides a platform that includes Akka, a separate open-source framework that provides actor-based concurrency.

Alternative communicating sequential processes (CSP) implementations for channel-based message passing are communicating Scala Objects.

Scala also comes with built-in support for data-parallel programming in Parallel Collections integrated into its Standard Library.

Scala Language example  

Scala as a programming language is broad, and it encompasses a wide area of codes. The language has a wide variety of regulations. Find below some of the code examples:-

  1. A scalable Language – It discusses things such as; a language that grows on you; what makes Scala scalable? Why Scala? Scala’s roots, then conclusion.
  2. First steps in Scala –the sample run of this chapter include five ideal steps when you set foot into Scala. In the order of the steps; Learn using Scala interpreter, Define some variables, Define some functions, Write some Scala scripts, Loop with while; decide with if, Iterate with for each and for.
  3. 6666
  4. Classes and Objects –Include; Classes, fields and methods, semicolon inference, singleton objects, A Scala application, The Application trait, and finally, conclusion.
  5. Basic Types and Operations-Entails; some basic types, Literals, Operators are methods, Arithmetic operations, Relational and logical operations, Bitwise operations, Object equality, Operator precedence, and associativity, Rich wrappers then enveloped by the conclusion.
  6. Functional objects
  7. Built-in control structures 
  8. Functions and closures
  9. Control Abstraction
  10. Composition and Inheritance 
  11. Scala’s Hierarchy 
  12. Traits 
  13. Packages and Imports
  14. Assertions and Unit Testing 
  15. Case Classes and Pattern Matching 
  16. Working with Lists
  17. Collections 
  18. Tasteful objects
  19. Type parameterization
  20. Abstract Members
  21. Implicit Conversions and Parameters
  22. Implementing Lists
  23. For Expressions Revisited
  24. Extractors
  25. Annotations 
  26. Abstract Members
  27. Working with XML
  28. ModularprogrammingUsing objects
  29. Object Equality
  30. Combining Scala and Java
  31. Actors and concurrency

How is Scala compiled?

Have you ever asked yourself what Scala compiler does during the compiling time? It is fascinating to get to know actually what Scala goes through during the process of compiling.

A close study of this activity reveals that the Scala compiler goes through 25 phases during the compiling time.

There are various bugs like slickness during the compiling time, which implicitly enable us to use this instead of case representation of which lack of order in HList increases more compiling time.

A compiler is divided into three parts: front end, middle end, and back end.

The front end is responsible for creating an AST tree and modifies it on some fundamental level.

The middle end, in turn, does some platform-independent optimizations (tail calls).

The back end does optimizations for specific CPUs, and then it generates assembly files.

Generally, the Scala compiler is organized somewhat differently; for instance, CPU-specific optimizations are delegated to JVM.

All the 25 phases are connected in a pipeline, and every stage performs transforms your code.

At the initial stages, intermediate compilation results become more complex as it is first created and typed. 

After the beginning stage, it simplifies as the compiler removes advanced language features.

Some of the compilation phases are parser, Namer, Typer, Package Objects, Pattern matching, Pickler, Uncurry, Tail calls, Specialize, Eraser, and posterasure Lambda lift, constructors, and flatten JVM.

-Parser, as the first phase, creates a non-typed AST using parser and scanner. When syntax errors are thrown though XMLs are translated, the functional code is desugared into more superficial structures.

-Namer, Typer, Package all form one object in the compiler code as they have many mutual dependencies. At first, the namer creates a symbols table; then in the next, there are two symbols table, one from namer and the other from typer .the latter phase adds more information to the table about values inside objects.

-Pattern matching desugars pattern into a sequence of ifs and else.

-Pickler phase performs serialization of classes into attributes that are used later during the bytecode creation.

-Uncurry phase entails removal of currying and some functional syntactic sugar.

-Tail calls phase optimizes tail recursion whereby in bytecode it is replaced with jumps, so the bytecode looks like a normal for looping action.

-Erasure and poster sure states that the use of generics or value in your code would lead to them being erased. The poster particular phase cleans up unnecessary code does some optimizations, and unboxes value classes.

Is Scala worth learning in 2020?

If you need a better match in programming, you should agree that it is actually worth learning.

Scala has proved its worth to the industry in the long term period. Most of the best and most significant companies in the world have employed Scala language.

Some of those companies that use Scala are Microsoft, Linkedln In, Twitter, Unicredit, Paypal, Twilio.

Some of their best programming libraries and tools of their kind are written in Scala. Framework stands out as some of their best in class.

Scala is one of the most expressive languages, for example, Infix operators, simple method naming, and the powerful type system.

Below are some of the reasons why Scala is worth learning :

  • Scala is widely used with a spark for real-time data analysis (Big data)
  • Scala supports both functional and OOPs concepts.
  • There are so many frameworks written in Scala like Akka, Play, Lift, Spark, etc.
  • Data streaming is possible with Akka using Scala.
  • Scala opening is more, but less experienced people are available.
  • Scala outdoes Java and Python in terms of speed.
  • Scala is very helpful in writing minor as well as extensive applications.
  • Scala is less verbose. 
  • Possibility of performing parallel batch processing in Scala
  • It is highly recommended for concurrency and distributed applications.

Learning Scala is worth it for someone interested in Programming. 


The term programming is indeed a broad scope beyond our reach but within our reach. Building small steps will prove to us that we can achieve much beyond our reach.

In short, Learning is a progressive activity that impacts our mind with knowledge. In recent times, the trending thing is data science, thus requiring us to acquire knowledge in this field. Various careers in this sector will enable us to broaden our capabilities and skills.

Programming as a career indeed is rather sweet, cool, and exciting in all the spheres you view. It further divides into several languages, which impact us with the skills required.

Scala is one of the best languages to learn as much as one can understand the Java language. Scala is an indispensable language in the world of programming though Java is the one primarily used.

Depending on the language you pick to learn, you should desire to learn Scala as it is worth being known.

Luis Gillman
Luis Gillman

Hi, I Am Luis Gillman CA (SA), ACMA
I am a Chartered Accountant (SA) and CIMA (SA) and author of Due Diligence: A strategic and Financial Approach.

The book was published by Lexis Nexis on 2001. In 2010, I wrote the second edition. Much of this website is derived from these two books.

In addition I have published an article entitled the Link Between Due Diligence and Valautions.

Disclaimer: Whilst every effort has been made to ensure that the information published on this website is accurate, the author and owners of this website take no responsibility  for any loss or damage suffered as a result of relience upon the information contained therein.  Furthermore the bulk of the information is derived from information in 2018 and use therefore is at your on risk. In addition you should consult professional advice if required.