Scheme Programming Language – Introduction
Unlike Assembly languages, Scheme Programming language is a high-level language. It can be more preferably called as a highly expressive language. The syntaxes are far easier to read, but not as easy as Python or Ruby. Scheme Programming language operates on data structures like vectors, strings, tuples, characters and numeric parts. The Scheme Programming language has rich data sets which make it extremely versatile. Programs written with scheme Programming are highly portable through various platforms.
So, what is Scheme Programming Language exactly?
We know that it’s not a beginner language. Then how does it tend to match up with the likes of Java, C or C++? The most basic interpreter used for Programming in Scheme is Dr. Racket which was previously known as PLT Scheme. It has a good IDLE inbuilt as well. It is actually a very simple language, and can even be treated as a beginner language.
The only thing is that the popularity and the hypes of Python, Ruby, and Perl have overshadowed the simplicity of Scheme Programming language. Unlike other languages, it doesn’t have too many syntaxes.
It has a specific set of syntaxes known as syntactic forms. If you have studied Python previously, you will understand that the interpretation form of scheme programming language examples requires experimentation to develop new methods. Though scheme programming is challenging at times, it requires one’s full potential and thorough knowledge, study, and practice.
A simple scheme program looks like this:
(define sqre
(lambda (n)
(* n n)))
This is a program where ‘sqre’ is a defined function to get the square of a number. You can then use the following in the interpreter to get the square.
>>>(sqre 4) => 16
>>>(sqre -9) => 81
Note: When you write scheme programs, you don’t need to use indentations. The Racket interpreter is smart enough to auto-indent the program. Parts written in Green are pieces of code, and black is the output above. Also, you can see that every piece of code needs to be enclosed in parenthesis, else it will simply return an error. I am using indentations just to make the code clearer.
A similar example for getting a reciprocal:
(define recpcl
(lambda (n)
(if (= n 0)
"Invalid denominator "
(/ 1 n))))
Here, recpcl is the short for reciprocal and it calculates 1/n where n is not equal to Zero for any number. If n is zero, it will return an error as “Invalid denominator”. And you can try this by typing:
4.5 (5,374 ratings)
View Course
(recpcl 3) => 1/3
(recpcl 9/4) => 4/9
(recpcl 0) =>"Invalid Denominator"
(recpcl (recpcl 2/3)) => 2/3
Implementation of Scheme programming language
Scheme Programming language is typically used to write to write text editing programs, analyzing and optimizing application based compilers, writing drivers for graphics cards, developing operating systems and many more.
Commercially, it is more useful for developing numerically based applications, to write programs to calculate large finance based tasks such as analyzing financial resources and its applications. Recently, it has also been used for the development of VR (virtual reality).
Applications written in scheme programming languages examples are easily available to port across different platforms on different architectures. This is because the machine dependencies are totally hidden from the programmer here. This portability can be exercised through a set of standard scheme programming language libraries with the help of basic mechanism for introducing new libraries and other level programs.
Gambit also known as Gambit-C (uses C for backend processing) is a free software which comprises of a compiler and an interpreter. It compiles scheme language to C. Normally you can write all those programs in Scheme language which you can write in C or Java. Just so that you know, Scheme programming language is a dialect from the family of Lisp. Macros in a scheme programming language are extremely powerful.
Scheme Programming language supports almost all of the programming protocols such as POP, ActiveX, SMTP, IMAP, HTTP, XML, and many more. These protocols are used daily to build real-world applications that are used all around the globe.
Performance and Efficiency
If you are an experienced programmer, then you may know that scheme programming language used to be slow. But however, that’s not the current case. All the recent compilers are extremely efficient and fast. These programs run at par with programs written in low-level languages (not exactly equal to the speed of assembly, but however almost near to it).
The reason why scheme programming language is fast because there are scheme code implementations which are extremely fast. Most of you may not know, but I have seen Chez scheme code being undoubtedly very fast. The reason being it’s a fast compiler which can compile up to 30,000 lines of scheme code per second into machine code. This kind of conversion is extremely fast which makes it possible to compete with machine code if not beat it.
But there is a catch here. Optimizing Scheme code is not easy. As a matter of fact, it’s far more tough to write a compiler code in the scheme than to write it in C. There are a lot of things that goes on here. Things like high order functions, data flow, type checking and all of these just make scheme programming language more complicated. A simple scheme compiler cannot perform all of the above front end optimizations of scheme programming language and the optimizations of C along with that.
Frankly speaking, if you ask people in scheme programming language, you won’t find any high-end performance implementation. The reason for that is because people usually tend to write small implementations and they don’t tend to use it for performance purpose.
People in scheme programming language, actually most of them don’t even care about performance. It is not because they don’t need it. It is because basic implementations of a scheme code are already fast enough for them.
However, following are some of the fast time compilers for Scheme:
- Stalin
- Chicken
- Gambit-C (or just Gambit)
- Bigloo
C vs Scheme Programming
Just in case, if you are a beginner and new to learning programming and you are planning to start with the scheme; I would rather suggest you, to begin with, HTDP (How to Design Programs). HDTP is based on scheme programming language, but it focuses more on the parts recursion. Its primary aim is to introduce you to a framework for solving problems that are generally applicable in the real world.
However, it can tend to get boring at first because most of the stuff appear repeated. But this kind of studious approach can make you solve tedious problems in an easy manner without the use of recursion and other tools. I don’t see any specific reason to not to learn both languages i.e. C and scheme language at the same time. If it was python rather than C, there could have been some issues.
But learning C and scheme language together would, however, seem tedious, but eventually, it will set a good foothold for programming. The reason for that is because C and Scheme are two different sides of the same coin. When I say different means, if you try to study both, there is hardly any chance that you would get confused since both of them have purely distinct syntaxes and formats.
But still, if you are considering learning only one language, then C is probably the right choice. If you know C, probably scheme language may get a bit easier to understand (this is supposing you are a pure beginner.)
Though it is obviously possible to learn both C and Scheme tutorials on a parallel basis, I would recommend learning as per your own method, but the time you hit a rough road, (when I say rough road, I mean hard to understand either language.) you should consider focusing one at a time. Learning HTDP is a great idea if you are totally new here.
If you are already familiar with C, then you should probably learn Scheme tutorial as well. The reason for that is FFI (Foreign Function Interfaces). It is provided by all of the implementations of Scheme programming language. This makes possible to quickly write a prototype in Scheme tutorial and optimize only a few portions of code in that program.
With this happening, you can recode the other non-optimized part in C and invoke these functions of C to Scheme language using Foreign Fish. Thus if you have learned C, then it will help you extremely to make your Scheme code as optimized as possible.
But if you are in the intermediate stage of learning, you may consider having to learn C. The point here is you should first know how to write programs and then start learning programming.
Other thoughts
Although Scheme Programming language is a pretty good language and one can use it as a beginner as well, however on the other hand, in the real world, people in the programming world tend to prefer the language with the imperative style. Most of them usually use C or C++. And programmers of C++ will seemingly discourage you from using math-based techniques for program design for one or the other reason.
No matter how good you are with recursion, it, however, won’t deliver a big role in writing imperative programs. As for me, I would always prefer Python as my primary high-level languages. There is no issue with Scheme tutorial, but when you write programs you need peace of mind. And for me, the call goes to C and Python, none else.
First Image Source: pixabay.com
Recommended Articles
This has been a basic guide to scheme programming language here we have discussed different programming languages which can be easier as compared to the scheme. You may also look at the following articles to learn more –