Blockchain CBDE - BTA Certified Blockchain Developer - Ethereum

to run tests quickly and especially for free, compared to continuous deployment on the MainNetwork. This way you save a lot of fees, time and costs.

to run tests in an environment where logging is activated. On the Main-Net you have no access to transaction logs and this is ultimately the information you need to debug your contracts.

to avoid regression bugs with contracts that are updated constantly on the main-net. Once you update a contract on the main-net, the address stays the same, but the code changes and this can have disastrous side-effects.

cannot receive Ether, not even by adding the payable modifier.

can contain as much logic as you want, but it’s better to keep it short and not exceed the gas stipend of 2300 gas.

can be used to avoid receiving ether.

to define a new datatype in Solidity, so you don't need to use objects of another contract.

to hold instances of other contracts.

to implement pointers to other contracts that can hold new datatypes.

are interrupting execution on error, because they throw an exception.

continuing execution on error silently, which is the reason why they are so dangerous.

returning Booleans to indicate an error during execution.

.send() throws an exception, while the other functions are returning Booleans during execution to indicate an error.

will cascade exceptions and address.transfer() will return a false on error.

will return false on error while address.transfer() will cascade transactions.

the library you use must make use of the JSON-RPC Interface of an Ethereum Node.

must Implement the Ethereum Protocol to connect to other Ethereum Nodes.

must use Web3.js, which is closed source to communicate to other Ethereum Nodes.

to contribute to the box community which is the distributed file system for truffle.

to start with a pre-configured environment for most web-development needs.

to use tools that makes boxing of Dapps for different platforms very easy.

1 Ether = 10^18 wei, 10^9 Gwei, 10^3 Finney

1 Ether = 10^19 wei, 10^13 Gwei, 10^3 Finney

1 Ether = 10^16 wei, 10^13 Gwei, 10^3 Finney

1 Ether = 10^18 wei, 10^6 Gwei, 10^6 Finney

is much better than Solidity and a viable alternative.

can be split across multiple files, but every contract must be in a file with the same name as the contract itself.

is another language similar to LLL, more secure than Solidity.

it's good to inform users about the updates via a newsletter.

it's good to have the ability to pause a contract in order to manage the money at risk.

Ethereum doesn't upgrade the platform. It's fixed and final.