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Diffstat (limited to 'docs/contracts.rst')
| -rw-r--r-- | docs/contracts.rst | 21 |
1 files changed, 14 insertions, 7 deletions
diff --git a/docs/contracts.rst b/docs/contracts.rst index 5f370951..c38fdb9d 100644 --- a/docs/contracts.rst +++ b/docs/contracts.rst @@ -179,7 +179,7 @@ and the default is ``internal``. .. note:: Everything that is inside a contract is visible to all external observers. Making something ``private`` - only prevents other contract from accessing and modifying + only prevents other contracts from accessing and modifying the information, but it will still be visible to the whole world outside of the blockchain. @@ -194,9 +194,16 @@ return parameter list for functions. function setData(uint a) internal { data = a; } uint public data; } + contract Caller { + function readData(){ + C c = new C(); + uint local = c.data(); // call accessor + local = f(7); // error + } + } Other contracts can call ``c.data()`` to retrieve the value of data in state -storage, but are not able to call ``f``. Contracts derived from ``c`` can call +storage, but are not able to call ``f``. Contracts derived from ``C`` can call ``setData`` to alter the value of ``data`` (but only in their own state). .. index:: ! accessor;function, ! function;accessor @@ -205,16 +212,16 @@ Accessor Functions ================== The compiler automatically creates accessor functions for -all public state variables. The contract given below will -have a function called ``data`` that does not take any -arguments and returns a uint, the value of the state +all public state variables. For the contract given below the compiler will +generate a function called ``data`` that does not take any +arguments and returns a ``uint``, the value of the state variable ``data``. The initialization of state variables can be done at declaration. The accessor functions have external visibility. If the symbol is accessed internally (i.e. without ``this.``), -it is a state variable and if it is accessed externally -(i.e. with ``this.``), it is a function. +it is evaluated as state variable and if it is accessed externally +(i.e. with ``this.``), it is evaluated as function. :: |