BlockChain

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Blockchain Coding

Blockchain Coding: The Many different Languages You Need! The blockchain technology is incredibly fascinating. It won’t be far-fetched to think of a future which will be built entirely on it. So, what do you need to learn in order to start developing on the blockchain? Which languages will give you the edge? In this guide, we will go through some of the more major ones.

Problems with developing blockchain software

Before we begin, let’s checkout some of the challenges that a blockchain developer faces. Creating and maintaining a public blockchain is not easy because of a number of reasons.

Reason #1: Security

Blockchains, as David Schwartz puts it, should be fortresses. Firstly, the code is public and open for all to see. Anyone can look over the code and check for bugs and vulnerabilities. However, unlike other open code resources, the downside of finding vulnerabilities on blockchain code is massive. Any programmer can hack in and get away with potentially millions and millions of dollars. Because of these legitimate security concerns, development on blockchain is usually very slow.

Reason #2: Resource Management

It is important to keep pace with the network. You cannot fall too far behind and not keep up with all the network demands. You should be well equipped to handle remote and local queries.

Reason #3: Performance

The blockchain must always perform at its highest possible capabilities, but for that to happen the language chosen must be extremely versatile. The thing is that there are certain tasks in the blockchain which are parallelizable whilst there are some tasks which can’t be done in parallel.

A good example of “parallelizable” task is digital signature verification. All that you need for signature verification is the key, transaction and the signature. With just three data you can conduct verifications in a parallelized manner.

However, not all the functions on a blockchain should be done that way. Think of transaction execution itself. Multiple transactions can’t be executed in parallel; it needs to be done one at a time to avoid errors like double spends. Some languages are good at parallel operations while some are good in non-parallel operations

Reason #4: Isolation

What is deterministic behavior?

  • If A + B = C, then no matter what the circumstances, A+B will always be equal to C. That is called deterministic behavior.
  • Hash functions are deterministic, meaning A’s hash will always be H(A).


So, in blockchain development, all transaction operations must be deterministic. You cannot have a transaction that behaves one way and then behaves another way the next day. Similarly, you cannot have smart contracts that work in two different ways in two different machines.

The only solution to this is isolation. Basically you isolate your smart contracts and transactions from non-deterministic elements.

Blockchain Development Languages

we have discussed the main problems that blockchain developers face. Now let’s finally check out some of the languages that the developers can use to code on the blockchain.

Language #1: C++

First and foremost, let’s start with the granddaddy of them all, the evergreen C++. C++ was created by Bjarne Stroustrup as an extension of the C language. The Language was designed to have the flexibility and efficiency of the C but with some major differences. The biggest difference between C and C++ is that while C is process-oriented, C++ is object oriented.

What this means is that, in C++, the data and functions are wrapped into one neat little package called “objects” which means that once an object is created, it can easily be called and reused in other programs, which greatly reduces coding time.

Let’s look at the simplest C++ program in the world. The “Hello World” program:

#include <iostream.h>
main()
{
cout << "Hello World!";
return 0;
}

This code will print: Hello World!

So, why do people still use C++ for coding? Surely there are way more glamorous languages now, why do people still insist on going back to C++? Why is the bitcoin blockchain coded on C++?

Well, as it happens, C++ has certain features that makes it very appealing. (Shout out Peter Wiulle and David Schwartz for the following explanation).

Feature #1: Memory Control

Not only should blockchains be secured fortresses but they should have effective resource management as well. A blockchain is supposed to interact with a lot of untrusted endpoints while still giving quick service to any and all nodes.

This quick and prompt service is critical for the success of a cryptocurrency like bitcoin. Remember, they are all based on the principle of “consensus”, all nodes on the network must accept and reject the exact same blocks, or else there could be a fork in the chain.

In order to satisfy all these demands and perform at the highest level, you need tight and complete control over CPU and memory usage. C++ gives that to its users.

Feature #2: Threading

As we have discussed before, one of the main challenges of the blockchain programming is the integration of tasks that parallelize well and the tasks that don’t parallelize. Most languages specialize in one, however C++’s threading ability is good enough to handle both parallel and non-parallel tasks. A thread is a set of instructions that can be executed simultaneously. Not only does C++ allow fir superb multithreading facilities with effective inter-thread communication, it also optimizes single-thread performance.

Feature #3: Move Semantics

One of the most interesting aspects of C++ is move semantics. Move semantics provides a way for the contents to be moved between objects rather than be copied outright. Let’s checkout the differences between copy semantics and move semantics. (Following data taken from Peter Alexander’s answer in “Stackoverflow”).

Copy Semantics:

assert(b == c);
a = b;
assert(a == b && b == c);

So what is happening here? The value of b goes into a and b remains unchanged at the end of the whole thing.

Now, consider this.

Move Semantics:

assert( b = = c);
move (a,b);
assert (a = =c );

What is happening here?

Can you see the difference between the two blocks of codes?

When we are using the move semantics, the value of “b” need not be the unchanged. That is the difference between copy semantics and move semantics. The biggest advantage of move semantics is that you can get copies of certain data only when you need them, which greatly decreases redundancy in the code and gives a huge performance boost. So as you can see, this efficient memory management and high performance are both desirable for the blockchain.

Feature #4: Compile Time Polymorphism

What is polymorphism?

Remember when we called C++ an “object oriented programming (OOP) language”? Polymorphism happens to be an OOP property. Using polymorphism, you use a particular feature in more than one ways. In C++ polymorphism can be used in two ways:

  • Compile time polymorphism.
  • Run time polymorphism.

Over here, we will only be focusing on compile time polymorphism. There are two ways that C++ implements compile time polymorphism:

  • Function Overloading.
  • Operator Overloading.


Function Overloading:

Function overloading is when you have many functions of the same name but with different parameter intake.

Consider this program:

#include <bits/stdc++.h>
using namespace std;

class A
{
void func (int x)  //first instance of the function takes only one integer value
{
cout<<x<<endl;
}

void func (double x) //second instance of the function takes only one double value
{
cout<<x<<endl;
}

void func (int x, int y) //third instance of the function takes two integer values
{
cout<<x=y<<endl;
}

}

int main()

{
A obj1 //making one object of the class A
//now we are going to call the functions
obj1.func(2);
obj1.func(2.65);
obj1.func(2,5);
return 0;
}

Now when you run this function the output will be:

  • 2
  • 2.65
  • 7

So, as you can see, the same function func() was used in 3 different ways.

Operator Overloading:

In C++ the same operator can have more than one meaning.

  • Eg. “+” can be used both for mathematical addition and for concatenation.
  • Concatenation basically means taking two strings and combining them as one.
  • So 3+4 = 7.

AND

  • Block+geeks = Blockgeeks.
  • The same operator, did two different functions, this is operator overloading.

The Compile time polymorphism helps a lot in blockchain development. It helps in putting responsibilities separately in various functions and, in turn, boosting the performance of the whole system.

Feature #5: Code Isolation

C++ has namespace features which can be imported from one program to another. Namespace helps in avoiding name collisions. Also, since C++ has classes, it can act as boundaries between various APIs and help in making clear separation.

A class in C++ is a user defined type or data structure declared with keyword class that has data and functions as its members. You can access the functions declared in the class by declaring objects of that particular class.

Feature #6: Maturity

The language is both mature and regularly updated. There are at least 3 solid compilers, as David Schwartz says, and the new features are aimed at solving real issues. Debuggers and analytical tools of all kinds are available for everything from performance profiling to automatic detection of issues of all kinds. This means the language is constantly growing to incorporate newer and better features.

Because of the above features, Satoshi Nakamoto chose C++ to be the base language of the bitcoin source code.






Language #2: Javascript

Language #3: Python

Language #4: Solidity

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