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-rw-r--r--docs/contracts.rst40
1 files changed, 31 insertions, 9 deletions
diff --git a/docs/contracts.rst b/docs/contracts.rst
index 121c4de0..f8a44fb3 100644
--- a/docs/contracts.rst
+++ b/docs/contracts.rst
@@ -40,7 +40,7 @@ This means that cyclic creation dependencies are impossible.
::
- pragma solidity ^0.4.16;
+ pragma solidity >0.4.21;
contract OwnedToken {
// TokenCreator is a contract type that is defined below.
@@ -52,7 +52,7 @@ This means that cyclic creation dependencies are impossible.
// This is the constructor which registers the
// creator and the assigned name.
- function OwnedToken(bytes32 _name) public {
+ 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,
@@ -679,7 +679,7 @@ candidate, resolution fails.
}
}
-Calling ``f(50)`` would create a type error since ``250`` can be implicitly converted both to ``uint8``
+Calling ``f(50)`` would create a type error since ``50`` can be implicitly converted both to ``uint8``
and ``uint256`` types. On another hand ``f(256)`` would resolve to ``f(uint256)`` overload as ``256`` cannot be implicitly
converted to ``uint8``.
@@ -803,7 +803,7 @@ as topics. The event call above can be performed in the same way as
}
where the long hexadecimal number is equal to
-``keccak256("Deposit(address,hash256,uint256)")``, the signature of the event.
+``keccak256("Deposit(address,bytes32,uint256)")``, the signature of the event.
Additional Resources for Understanding Events
==============================================
@@ -976,8 +976,31 @@ virtual method lookup.
Constructors
============
-A constructor is an optional function with the same name as the contract which is executed upon contract creation.
-Constructor functions can be either ``public`` or ``internal``.
+A constructor is an optional function declared with the ``constructor`` keyword which is executed upon contract creation.
+Constructor functions can be either ``public`` or ``internal``. If there is no constructor, the contract will assume the
+default constructor: ``contructor() public {}``.
+
+
+::
+
+ pragma solidity >0.4.21;
+
+ contract A {
+ uint public a;
+
+ constructor(uint _a) internal {
+ a = _a;
+ }
+ }
+
+ contract B is A(1) {
+ constructor() public {}
+ }
+
+A constructor set as ``internal`` causes the contract to be marked as :ref:`abstract <abstract-contract>`.
+
+.. note ::
+ Prior to version 0.4.22, constructors were defined as functions with the same name as the contract. This syntax is now deprecated.
::
@@ -995,7 +1018,6 @@ Constructor functions can be either ``public`` or ``internal``.
function B() public {}
}
-A constructor set as ``internal`` causes the contract to be marked as :ref:`abstract <abstract-contract>`.
.. index:: ! base;constructor
@@ -1009,11 +1031,11 @@ the base constructors. This can be done in two ways::
contract Base {
uint x;
- function Base(uint _x) public { x = _x; }
+ constructor(uint _x) public { x = _x; }
}
contract Derived is Base(7) {
- function Derived(uint _y) Base(_y * _y) public {
+ constructor(uint _y) Base(_y * _y) public {
}
}