Merge pull request #207 from ethereum/tuto3

docs/index.rst

 Remix - Solidity IDE
 ====================
 
+Remix is an IDE for the smart contract programming language Solidity and has
+an integrated debugger and testing environment.
+
+An up to date online version is accessible at `remix.ethereum.org <http://remix.ethereum.org>`_
+
+This page will host documentation and tutorial about features Remix provides.
+
+Please go to `solidity.readthedocs.io <http://solidity.readthedocs.io>`_ for any information regarding ``Solidity``
+
 Tutorial
 --------
 
@@ -8,3 +17,5 @@ Tutorial
    :maxdepth: 1
    
    tutorial_mist.rst
+   tutorial_debug.rst
+   tutorial_import.rst

docs/tutorial_debug.rst

+Debugging a Transaction
+=======================
+
+.. _tutorial-debug:
+
+The goal of this tutorial is to explain how to debug transaction using Remix.
+
+Start debugging
+---------------
+
+There are two different ways to start debugging, each way correspond to a different use case.
+
+From the Transaction GUI
+~~~~~~~~~~~~~~~~~~~~~~~~
+
+We will not explain in detail here how to write or deploy contract.
+Let us start with a basic contract (replace this one by yours):
+
+.. code-block:: none
+
+    contract Donation {
+        address owner;
+        event fundMoved(address _to, uint _amount);
+        modifier onlyowner { if (msg.sender == owner) _; }
+        address[] _giver;
+        uint[] _values;
+        
+        function Donation() {
+            owner = msg.sender;
+        }
+        
+        function donate() payable {
+            addGiver(msg.value);
+        }
+    
+        function moveFund(address _to, uint _amount) onlyowner {
+            uint balance = this.balance;
+            uint amount = _amount;
+            if (_amount <= this.balance) {
+                if (_to.send(this.balance)) {
+                    fundMoved(_to, _amount);    
+                } else {
+                    throw;
+                }
+            } else {
+                throw;
+            }
+        }
+        
+        function addGiver(uint _amount) internal {
+            _giver.push(msg.sender);
+            _values.push(_amount);
+        }
+    }
+    
+For the purpose of this tutorial we will run the ``JavaScript VM`` (that's the default mode if you don't use Remix with Mist or Metamask) which simulates a custom blockchain. You could do the same using a proper backend node.
+
+Let's deploy the contract:
+
+Right panel / Red button ``Create``
+
+.. image:: remix1.png
+
+Then we should call the ``Donate`` function (that will send Ether to the contract). 
+
+Let's set the amount of Ether:
+
+Right panel / second tab from the left - fill in the ´´value´´ input (´1 ether´ for instance)
+
+.. image:: remix_valueinput.png
+
+Then click on ``Donate``. As we are using the ``JavaScript VM``, everything goes almost instantly.
+
+Remix displays also some information related to each transaction result. On the right of each transaction result
+you can start debugging the corresponding transaction.
+
+.. image:: remix_startdebugging.png
+
+From the Debugger
+~~~~~~~~~~~~~~~~~
+
+The debugger can be found in the right panel / 5th tab from the left.
+
+You can start a debug session by providing either a ``transaction hash`` or a ``block number`` and ``transaction index``
+
+.. image:: remix3.png
+
+Click the ``play`` button to start debugging.
+
+Using the debugger
+------------------
+
+The debugger allows to see detailed informations about the transaction execution. It uses the editor (left panel) to display the location 
+in the source code where the current execution is.
+
+First the transaction panel display basic and simple information about the current transaction.
+
+.. image:: remix_debugtransactioninfo.png
+
+The navigation part contains a slider and buttons that can be used to step through the transaction execution.
+
+From the left to the right: 
+
+step over back, step into back, step into forward, step over forward, jump out (jump out of the current call), jump to the previous breakpoint, jump to the next breakpoint.
+
+.. image:: remix_navigation.png
+
+11 panels give detailed informations about the execution:
+
+Instructions
+~~~~~~~~~~~~
+
+.. image:: remix_debuginstructions.png
+
+This panel displays the bytecode of the current executing contract, the current step is highlighted.
+
+Important note: 
+When this panel is hidden, the slider will have a courser granularity and only stop at expression boundaries, even if they are compiled into multiple EVM instructions.
+When the panel is diplayed, it will be possible to step over every instruction, even those that refers to the same expression.
+
+Solidity Locals
+~~~~~~~~~~~~~~~
+
+.. image:: remix_soliditylocals.png
+
+That panel displays local variables associated with the current context.
+
+Solidity State
+~~~~~~~~~~~~~~
+
+.. image:: remix_soliditystate.png
+
+That panel displays state variables of the current executing contract.
+
+Low level panels
+~~~~~~~~~~~~~~~~
+
+These panels display low level informations about the execution:
+
+ - Stack
+ - Storages Changes
+ - Memory
+ - Call Data
+ - Call Stack
+ - Return Value (only if the current step is a RETURN opcode)
+ - Full Storages Changes (only at the end of the execution - display every storage change of every modified contract)
+ 
+Reverted Transaction
+~~~~~~~~~~~~~~~~~~~~
+
+A transaction could be reverted (either because of out of gas exception, Solidity ``throw`` or low level exception).
+
+In that case it is important to be aware of the exception and to locate where the exception is in the source code.
+
+Remix will warn you when the execution throws an exception. The ``warning`` button will jump to the last opcode before the exception happened.
+
+.. image:: remix_executionexception.png
+
+Breakpoints
+~~~~~~~~~~~
+
+The two last buttons from the navigation area are used to jump either back to the previous breakpoint or forward to the next breakpoint.
+
+Breakpoints can be added and removed by clicking on the line number.
+
+.. image:: remix_breakpoint.png
+
+When a debug session is started, the execution will jump to the first encountered breakpoint.
+
+Important note: 
+If you add a breakpoint to a line that declares a variable, it might be triggered twice: Once for initializing the
+variable to zero and second time for assigning the actual value.
+As an example, assume you are debugging the following contract:
+
+.. code-block:: none
+
+    contract ctr {
+        function hid () {
+            uint p = 45;
+            uint m;
+            m = 89;
+            uint l = 34;
+        }
+    }
+    
+And let's says that breakpoints are set for the lines 
+
+``uint p = 45;``
+
+``m = 89;``
+
+``uint l = 34;``
+
+
+then clicking on ``Jump to next breakpoint`` will stop at the following lines in the given order:
+
+ ``uint p = 45;``   (declaration of p)
+ 
+ ``uint l = 34;``   (declaration of l)
+ 
+ ``uint p = 45;``   (45 assigned to p)
+ 
+ ``m = 89;``    (89 assigned to m)
+ 
+ ``uint l = 34;``   (34 assigned to l)

docs/tutorial_import.rst

+Importing Source Files in Solidity
+==================================
+
+.. _tutorial-import:
+
+This tutorial will show you how to import local and external files.
+
+The compilation result will also contain contracts implemented in the imported files.
+
+For a detailed explanation of the ``import`` keyword see the ``Solidity``
+`documentation <http://solidity.readthedocs.io/en/develop/layout-of-source-files.html?highlight=import#importing-other-source-files>`_
+
+Importing a local file
+----------------------
+
+Other files in Remix can be imported just by specifying their path.
+Please use `./` for relative paths to increase portability.
+
+.. image:: tuto_basicimport.png
+
+Importing from Github
+----------------------
+
+It is possible to import files directly from github with URLs like
+``http://github.com/<owner>/<repo>/<path to the file>``.
+
+.. image:: tuto_importgit.png
+
+Importing from Swarm
+--------------------
+
+Files can be imported using all URLs supported by swarm. If you do not have a swarm
+node, swarm-gateways.net will be used instead.
+
+.. image:: tuto_importswarm.png

docs/tutorial_mist.rst

@@ -104,10 +104,10 @@ Right panel / second tab from the left, ``Transaction Origin`` should contain ac
 .. image:: remix5.png
 
 Developping contract / front end
--------------------------------
+--------------------------------
 
 Donation contract - Dapp Back end
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 Here is a sample solidity contract.
 
@@ -152,7 +152,7 @@ Copy and paste the following inside remix:
     
     
 Dapp Front end
-~~~~~~~~~~~~~
+~~~~~~~~~~~~~~
 
 and here is the front end:
 
@@ -233,7 +233,7 @@ you need to copy the new abi from remix to the front end.
 Deploying
 ---------
 
-Remix - Right panel / Red button ``Create``
+Right panel / Red button ``Create``
 
 .. image:: remix1.png