diff options
| -rw-r--r-- | docs/types.rst | 26 |
1 files changed, 18 insertions, 8 deletions
diff --git a/docs/types.rst b/docs/types.rst index b22ad7d4..1db35ced 100644 --- a/docs/types.rst +++ b/docs/types.rst @@ -312,12 +312,19 @@ If external function types are used outside of the context of Solidity, they are treated as the ``function`` type, which encodes the address followed by the function identifier together in a single ``bytes24`` type. +Note that public functions of the current contract can be used both as an +internal and as an external function. To use ``f`` as an internal function, +just use ``f``, if you want to use its external form, use ``this.f``. + Example that shows how to use internal function types:: + pragma solidity ^0.4.5; + library ArrayUtils { // internal functions can be used in internal library functions because // they will be part of the same code context function map(uint[] memory self, function (uint) returns (uint) f) + internal returns (uint[] memory r) { r = new uint[](self.length); @@ -327,8 +334,9 @@ Example that shows how to use internal function types:: } function reduce( uint[] memory self, - function (uint) returns (uint) f + function (uint x, uint y) returns (uint) f ) + internal returns (uint r) { r = self[0]; @@ -336,7 +344,7 @@ Example that shows how to use internal function types:: r = f(r, self[i]); } } - function range(uint length) returns (uint[] memory r) { + function range(uint length) internal returns (uint[] memory r) { r = new uint[](length); for (uint i = 0; i < r.length; i++) { r[i] = i; @@ -346,7 +354,7 @@ Example that shows how to use internal function types:: contract Pyramid { using ArrayUtils for *; - function pyramid(uint l) return (uint) { + function pyramid(uint l) returns (uint) { return ArrayUtils.range(l).map(square).reduce(sum); } function square(uint x) internal returns (uint) { @@ -359,14 +367,16 @@ Example that shows how to use internal function types:: Another example that uses external function types:: + pragma solidity ^0.4.5; + contract Oracle { struct Request { bytes data; - function(bytes) external callback; + function(bytes memory) external callback; } Request[] requests; event NewRequest(uint); - function query(bytes data, function(bytes) external callback) { + function query(bytes data, function(bytes memory) external callback) { requests.push(Request(data, callback)); NewRequest(requests.length - 1); } @@ -377,12 +387,12 @@ Another example that uses external function types:: } contract OracleUser { - Oracle constant oracle = 0x1234567; // known contract + Oracle constant oracle = Oracle(0x1234567); // known contract function buySomething() { - oracle.query("USD", oracleResponse); + oracle.query("USD", this.oracleResponse); } function oracleResponse(bytes response) { - if (msg.sender != oracle) throw; + if (msg.sender != address(oracle)) throw; // Use the data } } |