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diff --git a/docs/frequently-asked-questions.rst b/docs/frequently-asked-questions.rst index a6bead29..6a2fe685 100644 --- a/docs/frequently-asked-questions.rst +++ b/docs/frequently-asked-questions.rst @@ -9,17 +9,6 @@ This list was originally compiled by `fivedogit <mailto:fivedogit@gmail.com>`_. Basic Questions *************** -Example contracts -================= - -There are some `contract examples <https://github.com/fivedogit/solidity-baby-steps/tree/master/contracts/>`_ by fivedogit and -there should be a `test contract <https://github.com/ethereum/solidity/blob/develop/test/libsolidity/SolidityEndToEndTest.cpp>`_ for every single feature of Solidity. - -Create and publish the most basic contract possible -=================================================== - -A quite simple contract is the `greeter <https://github.com/fivedogit/solidity-baby-steps/blob/master/contracts/05_greeter.sol>`_ - Is it possible to do something on a specific block number? (e.g. publish a contract or execute a transaction) ============================================================================================================= @@ -40,9 +29,9 @@ Is there a decompiler available? ================================ There is no exact decompiler to Solidity, but -`Porosity <https://github.com/comaeio/porosity>`_ is close. -Because some information like variable names, comments, and -source code formatting is lost in the compilation process, +`Porosity <https://github.com/comaeio/porosity>`_ is close. +Because some information like variable names, comments, and +source code formatting is lost in the compilation process, it is not possible to completely recover the original source code. Bytecode can be disassembled to opcodes, a service that is provided by @@ -74,25 +63,6 @@ has it (which includes `Remix <https://remix.ethereum.org/>`_), then ``contractname.kill.sendTransaction({from:eth.coinbase})``, just the same as my examples. -Store Ether in a contract -========================= - -The trick is to create the contract with ``{from:someaddress, value: web3.toWei(3,"ether")...}`` - -See `endowment_retriever.sol <https://github.com/fivedogit/solidity-baby-steps/blob/master/contracts/30_endowment_retriever.sol>`_. - -Use a non-constant function (req ``sendTransaction``) to increment a variable in a contract -=========================================================================================== - -See `value_incrementer.sol <https://github.com/fivedogit/solidity-baby-steps/blob/master/contracts/20_value_incrementer.sol>`_. - -Get a contract to return its funds to you (not using ``selfdestruct(...)``). -============================================================================ - -This example demonstrates how to send funds from a contract to an address. - -See `endowment_retriever <https://github.com/fivedogit/solidity-baby-steps/blob/master/contracts/30_endowment_retriever.sol>`_. - Can you return an array or a ``string`` from a solidity function call? ====================================================================== @@ -542,12 +512,27 @@ contract level) with ``arrayname.length = <some new length>;``. If you get the :: - int8[] memory memArr; // Case 1 - memArr.length++; // illegal - int8[5] storageArr; // Case 2 - somearray.length++; // legal - int8[5] storage storageArr2; // Explicit case 2 - somearray2.length++; // legal + // This will not compile + + pragma solidity ^0.4.18; + + contract C { + int8[] dynamicStorageArray; + int8[5] fixedStorageArray; + + function f() { + int8[] memory memArr; // Case 1 + memArr.length++; // illegal + + int8[5] storage storageArr = fixedStorageArray; // Case 2 + storageArr.length++; // illegal + + int8[] storage storageArr2 = dynamicStorageArray; + storageArr2.length++; // legal + + + } + } **Important note:** In Solidity, array dimensions are declared backwards from the way you might be used to declaring them in C or Java, but they are access as in |