Solidity News Monday, July 16
- Unable to declare public mapping in Solidity
ethereum, solidity, contractdevelopment, mapping
- How does EtherDelta migrates mapping?
ethereum, solidity, mapping, etherdelta, migration
- What does it mean when a function is called in the head of constructor() function?
ethereum, solidity, function
- In solidity smart contracts how do you access internal state variables declared in the constructor?
- Truffle – Transfer leads to “Error: VM Exception while processing transaction: revert”
ethereum, solidity, truffle
- Calling function from ERC721Token reverts
ethereum, solidity, dapps
- Data Blockchain ICO bench, DBC ICO, DBCC Coins
- The problem here seems to be with the getters that are created when you declare the variables public, changing the visibility to internal cancels the error.
- In this answer it is explained that passing nested arrays is the problem.
- Note that in both cases adding a fix-length variable to the structs cancels the errors.
@StackEthereum: Unable to declare public mapping in Solidity https://t.co/WeOXBW0ohA #ethereum #solidity #contractdevelopment #mapping
- I’m looking at EtherDelta contract, and — provided it had been migrated several times in the past and probably foresees future migrations — I’m confused as I don’t see any method by which the owner of the contract can migrate the data.
- They must have a list of all the addresses in the mapping in order to migrate the data to a new version of the contract, don’t they?
- Yet it is missing from the contract.
@StackEthereum: How does EtherDelta migrates mapping? https://t.co/nTgiJw5LBS #ethereum #solidity #mapping #etherdelta #migration
- I’m reading through some smart contracts and I noticed functions being called in the head of the constructor function, like MarginAdmin() in the following example.
- In this case, MarginAdmin is another solidity contract that is being imported into this file.
- What does this mean when a function gets called like this in the head of constructor function?
@StackEthereum: What does it mean when a function is called in the head of constructor() function? https://t.co/AeFMIoS3Z7 #ethereum #solidity #function
- You should simply include those variables outside of the constructor function as a global variable for the contract.
- Take a look at a pretty simple to understand, and very commonly used contract: you can see the variable lives outside the constructor function, and instead just gets set (rather than declared) within the constructor.
- Would this pattern work for your scenario, or is there some specific need to initialize the variable as a part of the constructor function?
@StackEthereum: In solidity smart contracts how do you access internal state variables declared in the constructor? https://t.co/2gEql5yqfF #ethereum
@StackEthereum: Truffle – Transfer leads to “Error: VM Exception while processing transaction: revert” https://t.co/XQOGDY3cv2 #ethereum #solidity #truffle
@StackEthereum: Calling function from ERC721Token reverts https://t.co/gmAk8lUSgV #ethereum #solidity #dapps
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@Gawiga: Parte 0 – Introdução ao Solidity https://t.co/vQb0oJtCKH
@doesitforu: Books, in the plural lose their solidity of substance and become a gas, filling all available space. https://t.co/ho6oT49dep #audibledownload
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