Languages supported by Ethereum

2.

what is Ethereum:

Ethereum is an innovation based on the application of technologies and concepts in bitcoin to computers. Ethereum itself imitates a lot of bitcoin technology to maintain the computer platform. Blockchain technology is one of them
Ethereum platform can safely run any program users want

advantages of Ethereum over other competitive currencies before Ethereum appeared, some digital currencies imitated bitcoin. However, these projects have their own shortcomings, they can only support one or several specific applications at the same time< However, the reason why Ethereum can surpass the limitations of these projects in the past is because of the core idea of Ethereum

what Ethereum wants to implement is a blockchain protocol with built-in programming language. Since it supports programming language, in theory, any blockchain application can be defined with this language, and then run on Ethereum's blockchain protocol as an application

The design of Ethereum is very flexible and adaptable

Ethereum target sets the advantages of blockchain technology, in order to add the advantages of blockchain, such as decentralization, openness and security, to almost all computing fields

blockchain applications of Ethereum

Ethereum has many blockchain applications, such as digital applications of gold and stocks, financial derivatives applications, DNS and digital authentication, etc

Ethereum has achieved more than 100 blockchain applications by many start-ups

Ethereum has also been closely watched by some financial institutions, banking consortia (such as R3), as well as large companies like Samsung, Deloitte, RWE and IBM. As a result, a number of blockchain applications such as simplified and automated financial transactions, merchant loyalty index tracking, and gift cards designed to achieve decentralization of electronic transactions have emerged

the relationship between Ethereum and blockchain:

Ethereum is a programmable blockchain

Ethereum does not give users a series of preset operations (such as bitcoin transaction), but allows users to create complex operations according to their own wishes

in this way, Ethereum can be used as a platform for various types of decentralized blockchain applications, including but not limited to cryptocurrency

like other blockchains, Ethereum also has a peer-to-peer network protocol. Ethereum blockchain database is maintained and updated by many nodes connected to the network. Each network node runs the Ethereum simulator and executes the same instructions. Therefore, people sometimes call Ethereum "world computer"

3. Go full stack + blockchain course:
a total of 22 weeks, divided into five stages,
the first stage is 4 weeks, go language foundation and network concurrency, learning the introctory go language,
the second stage is 4 weeks, go language practical web development, crawler development, cryptography, consensus algorithm, realizing lightweight public chain, learning the website and crawler that can develop golang, Achieve lightweight blockchain
stage 3, 4-week Ethereum source code analysis and smart contract DAPP development, master Ethereum core and smart contract development, as well as blockchain,
stage 4, 4-week super ledger, bitcoin EOS, source code analysis and smart contract practice, master super ledger development, cat bitcoin, bifurcated EOS after learning, As well as DAPP development of smart contract
phase 5, 6-week project practice, five enterprise level projects, and one year of blockchain project experience after learning
from the characteristics of the language itself, go is a very efficient language, which highly supports concurrency. Go language itself pays more attention to distributed system, and concurrency processing is relatively good, such as advertising and search, That kind of high concurrency server
go language advantages:
excellent performance, can be directly compiled into machine code, does not rely on other libraries, go is extremely fast. Its performance is similar to Java or C + +
concurrency is supported at the language level, which is the biggest feature of go. It is born to support concurrency, and go is the concurrency supported in gene, which can make full use of multi-core and make it easy to use concurrency
the built-in runtime supports garbage collection, which is one of the features of dynamic language. Although GC is not perfect at present, it is enough to cope with most of the situations we can encounter, especially GC after go1.1
it's easy to learn. The authors of go language all have the gene of C, so go naturally has the gene of C. There are 25 go keywords, but the expressive ability is very strong. It almost supports most of the features you've seen in other languages: inheritance, overloading, object, etc
rich standard libraries, go has built a large number of libraries, especially the network library, which is also my favorite part< As like as two peas, br / > built-in powerful tools, Go language is built with many tools chain, the best should be gofmt tools, automatic formatting code, make team review become so simple, code format is exactly the same, it is very difficult to think differently.
cross platform compilation and fast compilation. Compared with the sluggish compilation speed of Java and C + +, the fast compilation time of go is a major efficiency advantage
disadvantages of go language:
package management: package management of go language is absolutely not perfect. By default, it has no way to make a specific version of the dependency library, nor can it create replicable builds. In contrast, python, node and Ruby all have better package management systems. However, with the right tools, the package management of go language can also perform well
lack of development framework: go language does not have a major framework, such as Ruby's rails framework, Python's Django framework or PHP's laravel. This is a heated discussion in the go language community, because many people think that we should not start with using frameworks. This is true in many cases, but if you just want to build a simple crud API, it's much easier to use Django / djrf, rails laravel, or Phoenix
exception handling: go language can help developers deal with compilation errors by simply returning errors (or call stack) through functions and expected calling codes. Although this method is effective, it is easy to lose the scope of the error, so it is difficult to provide meaningful error information to users. Error package can solve this problem by allowing us to add context and stack trace to return error
another problem is that we may forget to handle errors. Static analysis tools such as errcheck and megacheck can avoid these errors. Although these solutions are very effective, they may not be the right way.

4.

Ethereum is an open source public blockchain platform with smart contract function. It provides decentralized virtual machine (Ethereum virtual machine) to process point-to-point contract through its special cryptocurrency ether (also known as "Ethereum")

The token on the

blockchain is called ether, and the code is eth. It can be traded in many foreign exchange markets of cryptocurrency, and it is also the medium used to pay transaction fees and computing services on Ethereum

the concept of Ethereum was first proposed by vitalik buterin, a programmer, from 2013 to 2014, inspired by bitcoin, with the general meaning of "next generation cryptocurrency and decentralized application platform", and began to develop through ICO crowdfunding in 2014. As of February 2018, Ethernet is the second highest cryptocurrency in market value, second only to bitcoin

extended data:

Ethereum platform has no characteristics and value. Like programming languages, it's up to entrepreneurs and developers to decide what to use. However, it is clear that some application types benefit more from the functions of Ethereum than others. Ethereum is especially suitable for those applications that automatically interact directly between points or promote group coordination activities across networks

for example, coordinate the application of point-to-point market, or the automation of complex financial contracts. Bitcoin enables indivials to exchange money without the help of financial institutions, banks or governments. The impact of Ethereum may be more profound

in theory, any complex financial activities or transactions can be automatically and reliably carried out on Ethereum with coding. In addition to financial applications, any application scenario with high requirements for trust, security and persistence, such as asset registration, voting, management and Internet of things, will be affected by Ethereum platform on a large scale

5.

1. about the variability of blockchain

2. eth, if most people agree to modify the chain, that is, variability, then they can modify the blockchain records and contracts

3. etc, blockchain records and contracts can't be modified, that is, they can't be tampered with

4. here are the advantages and disadvantages of the two methods

   The advantage of

5. variability is that people can make timely changes to make the right decisions. Therefore, modifying the specification is more practical than finding loopholes

6. non modifiability means that no matter how smart people are at that time, it is impossible not to make mistakes. Therefore, when problems arise in this scheme, it is best to find and solve the loopholes through the existing legal framework

7. differences in development

8. eth, whether it is intentionally arranged or since its birth, the core decisions of blockchain are made by Ethereum foundation with the participation of the community and most of them are developed by it

9. etc, the decision-making of blockchain is mainly decided by the feedback of three loose, collaborative teams with community participation

10. in any case, anyone can put forward improvement suggestions for the two kinds of blockchains. This is the benefit of open source, and it is also very common. You will find that developers of the two chains communicate with each other through GitHub and reddit. I hope to improve the frequency of communication in order to achieve the common goal

11. about compatibility

12. at present, the two kinds of blockchains are compatible with each other. Contracts or applications written by eth can be applied on etc, and vice versa

13. eth, focusing on ewasm, is committed to providing a platform for more and more developers, while the issue of contract security is secondary, such as viper

14. etc focuses on making developers create more secure contracts, such as viper, iohk research, at the cost of consuming the number of potential developers

15. it's obvious that both chains can accept each other, regardless of whether their wishes are the same or not. My view is that the number of developers is not necessarily related to the quality of the proct

16. about the transaction speed

17. eth, the average is 25 seconds, which will be shortened after upgrading

18. etc, with an average time of 14 seconds, maintained at 10-14 seconds after upgrade, according to ecip-1010 and ecip-1036 protocols

19. about the block capacity

20. eth, with the daily trading volume of eth graally reaching 5 million, the block capacity is graally saturated. This situation is similar to the recent transaction cost of bitcoin. This problem can be solved by expanding the block capacity by increasing the default fuel limit

21. ETC­， At present, there is still a lot of room for block capacity. As more and more people accept etc, the block capacity will also increase, just like eth

22. about community

23. eth, mainly discuss on reddit

24. etc, mainly discuss on slack

25. about monetary policy

26. eth, the planned supply is growing steadily, resulting in an average inflation of 3% in eth blockchain in its life cycle

27. etc, before 2025, inflation will reach 3%, and then the total supply will reach 200 million etc, and then there will be deflation

    As for the regional distribution of trading volume, China accounts for 20%, South Korea 25% and the United States 25%
    In etc, China accounts for 50%, South Korea 25% and the United States 10%
    About securities, at present, investors do not have the option to trade securities. Recently, one of eth's ETFs, trading open-end index funds, was denied by the regulators

28. etc owns etc trading trust, which allows investors to own etc instead of the asset itself

6. 1. What is the ether classic<

etc (Ethereum Classic) is a bifurcated currency that Ethereum hard bifurcates after 1920000 blocks, and its function is very similar to Ethereum. Etc adheres to the concept of decentralization and supports the consensus mechanism of blockchain guarantee. Etc firmly believes that once the blockchain starts to run, its development direction will not be controlled by any central team, but will be determined by the consensus of the people participating in the whole network and the consensus of the computing power of the whole network

the Ethereum blockchain hard branching in July 2016 aims to transfer the Dao funds stolen by hackers to an account controlled by investors, and let the old transaction records be forgotten by history. Most Ethereum developers are involved in the reversal, as are exchanges, startups and other members of the ecosystem. A few days later, the project returned to normal. But not everyone wants to forget the old record. As a result, a small number of miners continued to use the original blockchain as a protest. They described the hard fork as a capital withdrawal for the abandoned project of the Dao. So Ethereum classic (etc) was born

2. Detailed parameters

Chinese Name: Ethereum classic English Name: Ethereum classic English abbreviation: etc

developer: Ethereum Classic team core algorithm: ethash consensus proof: POW

release date: 2016 / 7 / 20 block time: About 15-17 seconds / block

total currency: fixed at 210 million, up to 230 million, Every 5 million blocks decelerate by 20%, and the first proction rection is expected to be in December 2017

main features: independent cryptocurrency

7. The mps() function performs the same serialization as the mp() function. Instead of accepting stream objects and saving serialized data to disk files, this function simply returns serialized data
the loads() function performs the same deserialization as the load() function. Instead of accepting a stream object and reading the serialized data from a file, it accepts the str object containing the serialized data and returns the object directly.

8. It is suggested that you buy an analysis book with examples and take a look at the above answer format, which should be helpful.
when answering questions, you should draw a stress analysis diagram and mark the direction of the force.
1, Secondly, it is clear which direction the object is in, who is exerting the force on it, and how much the force is.
3. According to Newton's law of mechanics and the conditions in the problem, the equation is listed, and the final result is obtained.
the knowledge points commonly used are: integral method and isolation method, the composition and decomposition of force, The following is a mechanical problem I have answered, hoping to give you some inspiration.
1. On the horizontal plane, there are rectangular blocks a and B in contact with each other, m (a) = 6kg, m (b) = 4kg, a horizontal right force of 5N acts on a, making them accelerate together, then the force between AB is:
analysis: let the dynamic friction coefficient be u, and the friction coefficient be 0, If the acceleration is a
and ab is regarded as a whole, and the force analysis is
then AB is subjected to the horizontal left friction F1 = u · (MA + MB) = 10u, and the horizontal right thrust f = 5N
then the acceleration a = (f-f1) ÷( mA+mB)=(5-10u) ÷ 10
according to the force analysis of B, it is known that B is pushed horizontally to the right by a, and the friction force to the left is F2 = u · MB = 4U
then the acceleration a = (f-f2) ÷ mB= (F-4u ) ÷ 4
connect the two formulas to get (5-10u) ÷ 10 = (F-4u ) ÷ 4
then f = 2n

9.

Solidness language is a special language for writing and executing smart contracts. It is a contract oriented high-level language running on the basis of Ethereum virtual machine. It was first proposed by the former CTO and co-founder Gavin wood of Ethereum in August 2014. Later, Ethereum developers set up a special team to continuously improve solidness language, At present, it is still under development and optimization. The development storage area on GitHub is HTPs / github.com/thereum/solidness. Here we can learn the most comprehensive details and related documents about the development and iteration process of solidness language. In terms of language style, solid language is deeply influenced by C + +, Python and JavaScript. It is a static programming language, compiled in bytecode mode, so it can run on Ethereum virtual machine. Gavin wood uses the syntax rules of ECMAScript scripting language of JavaScript for reference when developing solid language, which makes it somewhat similar to the existing web development language, but it is quite different. For example, solid language has static type, variable return function and so on. The most important point is that solid language can write contracts with self executing business logic and embedded in smart contracts. Therefore, it is not only one of the basic programming languages of Ethereum, but also the basic programming languages of most other Ethereum based blockchain procts (blockchain 2.0) with smart contracts, It is widely used in the vast majority of blockchain procts, such as hyperledger project, which is developed with soliditv language

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