diff options
Diffstat (limited to 'docs/contracts.rst')
| -rw-r--r-- | docs/contracts.rst | 33 |
1 files changed, 20 insertions, 13 deletions
diff --git a/docs/contracts.rst b/docs/contracts.rst index d4160eac..4d439b26 100644 --- a/docs/contracts.rst +++ b/docs/contracts.rst @@ -50,7 +50,7 @@ This means that cyclic creation dependencies are impossible. pragma solidity >=0.4.22 <0.6.0; contract OwnedToken { - // TokenCreator is a contract type that is defined below. + // `TokenCreator` is a contract type that is defined below. // It is fine to reference it as long as it is not used // to create a new contract. TokenCreator creator; @@ -61,14 +61,18 @@ This means that cyclic creation dependencies are impossible. // creator and the assigned name. constructor(bytes32 _name) public { // State variables are accessed via their name - // and not via e.g. this.owner. This also applies - // to functions and especially in the constructors, - // you can only call them like that ("internally"), - // because the contract itself does not exist yet. + // and not via e.g. `this.owner`. Functions can + // be accessed directly or through `this.f`, + // but the latter provides an external view + // to the function. Especially in the constructor, + // you should not access functions externally, + // because the function does not exist yet. + // See the next section for details. owner = msg.sender; + // We do an explicit type conversion from `address` // to `TokenCreator` and assume that the type of - // the calling contract is TokenCreator, there is + // the calling contract is `TokenCreator`, there is // no real way to check that. creator = TokenCreator(msg.sender); name = _name; @@ -86,10 +90,11 @@ This means that cyclic creation dependencies are impossible. // Only the current owner can transfer the token. if (msg.sender != owner) return; - // We also want to ask the creator if the transfer - // is fine. Note that this calls a function of the - // contract defined below. If the call fails (e.g. - // due to out-of-gas), the execution also fails here. + // We ask the creator contract if the transfer + // should proceed by using a function of the + // `TokenCreator` contract defined below. If + // the call fails (e.g. due to out-of-gas), + // the execution also fails here. if (creator.isTokenTransferOK(owner, newOwner)) owner = newOwner; } @@ -100,8 +105,8 @@ This means that cyclic creation dependencies are impossible. public returns (OwnedToken tokenAddress) { - // Create a new Token contract and return its address. - // From the JavaScript side, the return type is simply + // Create a new `Token` contract and return its address. + // From the JavaScript side, the return type is // `address`, as this is the closest type available in // the ABI. return new OwnedToken(name); @@ -113,12 +118,14 @@ This means that cyclic creation dependencies are impossible. tokenAddress.changeName(name); } + // Perform checks to determine if transferring a token to the + // `OwnedToken` contract should proceed function isTokenTransferOK(address currentOwner, address newOwner) public pure returns (bool ok) { - // Check some arbitrary condition. + // Check an arbitrary condition to see if transfer should proceed return keccak256(abi.encodePacked(currentOwner, newOwner))[0] == 0x7f; } } |