Update metadata documentation

Changelog.md

@@ -1,7 +1,7 @@
 ### 0.4.7 (unreleased)
 
 Features:
- * Code generator: Inject the swarm hash of a metadata file into the bytecode.
+ * Code generator: Inject the Swarm hash of a metadata file into the bytecode.
  * Optimizer: Some dead code elimination.
 
 Bugfixes:

docs/miscellaneous.rst

@@ -236,21 +236,21 @@ If ``solc`` is called with the option ``--link``, all input files are interprete
 Contract Metadata
 *****************
 
-The Solidity compiler automatically generates a json file, the
+The Solidity compiler automatically generates a JSON file, the
 contract metadata, that contains information about the current contract.
-It can be used to query the compiler version, the sourcecode, the ABI
+It can be used to query the compiler version, the sources used, the ABI
 and NatSpec documentation in order to more safely interact with the contract
 and to verify its source code.
 
-The compiler appends a swarm hash (32 bytes) of that file to the end of the
+The compiler appends a Swarm hash of the metadata file to the end of the
 bytecode (for details, see below) of each contract, so that you can retrieve
 the file in an authenticated way without having to resort to a centralized
 data provider.
 
-Of course, you have to publish the metadata file to swarm (or some other service)
+Of course, you have to publish the metadata file to Swarm (or some other service)
 so that others can access it. The file can be output by using ``solc --metadata``
 and the file will be called ``ContractName_meta.json``.
-It will contain swarm references to the source code, so you have to upload
+It will contain Swarm references to the source code, so you have to upload
 all source files and the metadata file.
 
 The metadata file has the following format. The example below is presented in a
@@ -282,12 +282,13 @@ Comments are of course also not permitted and used here only for explanatory pur
           // Required: keccak256 hash of the source file
           "keccak256": "0x123...",
           // Required (unless "content" is used, see below): URL to the
-          // source file, protocol is more or less arbitrary, but a swarm
+          // source file, protocol is more or less arbitrary, but a Swarm
           // URL is recommended
           "url": "bzzr://56ab..."
         },
         "mortal": {
-          "keccak256": "0x123...",
+          // Required: keccak256 hash of the source file
+          "keccak256": "0x234...",
           // Required (unless "url" is used): literal contents of the source file
           "content": "contract mortal is owned { function kill() { if (msg.sender == owner) selfdestruct(owner); } }"
         }
@@ -298,13 +299,16 @@ Comments are of course also not permitted and used here only for explanatory pur
         // Required for Solidity: Sorted list of remappings
         remappings: [ ":g/dir" ],
         // Optional: Optimizer settings (enabled defaults to false)
-        optimizer: {enabled: true, runs: 500},
+        optimizer: {
+          enabled: true,
+          runs: 500
+        },
         // Required for Solidity: File and name of the contract or library this
         // metadata is created for.
         compilationTarget: {
           "myFile.sol": "MyContract"
         },
-        // Required for Solidity: Addresses for libraries
+        // Required for Solidity: Addresses for libraries used
         libraries: {
           "MyLib": "0x123123..."
         }
@@ -326,7 +330,7 @@ Encoding of the Metadata Hash in the Bytecode
 ---------------------------------------------
 
 Because we might support other ways to retrieve the metadata file in the future,
-the mapping ``{"bzzr0": <swarm hash>}`` is stored
+the mapping ``{"bzzr0": <Swarm hash>}`` is stored
 [CBOR](https://tools.ietf.org/html/rfc7049)-encoded. Since the beginning of that
 encoding is not easy to find, its length is added in a two-byte big-endian
 encoding. The current version of the Solidity compiler thus adds the following
@@ -334,35 +338,33 @@ to the end of the deployed bytecode::
 
     0xa1 0x65 'b' 'z' 'z' 'r' '0' 0x58 0x20 <32 bytes swarm hash> 0x00 0x29
 
-So in order to retrieve the data, you can check the end of the deployed
-bytecode to match that pattern and use the swarm hash to retrieve the
-file.
+So in order to retrieve the data, the end of the deployed bytecode can be checked
+to match that pattern and use the Swarm hash to retrieve the file.
 
 Usage for Automatic Interface Generation and NatSpec
 ----------------------------------------------------
 
 The metadata is used in the following way: A component that wants to interact
-with a contract (e.g. mist) retrieves the code of the contract, from that
-the swarm hash of a file which is then retrieved.
+with a contract (e.g. Mist) retrieves the code of the contract, from that
+the Swarm hash of a file which is then retrieved.
 That file is JSON-decoded into a structure like above.
 
-The component can then use the abi to automatically generate a rudimentary
+The component can then use the ABI to automatically generate a rudimentary
 user interface for the contract.
 
-Furthermore, mist can use the userdoc to display a confirmation message to the user
+Furthermore, Mist can use the userdoc to display a confirmation message to the user
 whenever they interact with the contract.
 
 Usage for Source Code Verification
 ----------------------------------
 
-In order to verify the compilation, sources can be retrieved from swarm
+In order to verify the compilation, sources can be retrieved from Swarm
 via the link in the metadata file.
 The compiler of the correct version (which is checked to be part of the "official" compilers)
 is invoked on that input with the specified settings. The resulting
 bytecode is compared to the data of the creation transaction or CREATE opcode data.
-This automatically verifies the metadata since
-its hash is part of the bytecode.
-Excess data is constructor input data which should be decoded
+This automatically verifies the metadata since its hash is part of the bytecode.
+Excess data corresponds to the constructor input data, which should be decoded
 according to the interface and presented to the user.
 
 

solc/CommandLineInterface.cpp

@@ -482,7 +482,7 @@ Allowed options)",
 		(g_argSignatureHashes.c_str(), "Function signature hashes of the contracts.")
 		(g_argNatspecUserStr.c_str(), "Natspec user documentation of all contracts.")
 		(g_argNatspecDevStr.c_str(), "Natspec developer documentation of all contracts.")
-		(g_argMetadata.c_str(), "Combined metadata JSON whose swarm hash is stored on-chain.")
+		(g_argMetadata.c_str(), "Combined Metadata JSON whose Swarm hash is stored on-chain.")
 		("formal", "Translated source suitable for formal analysis.");
 	desc.add(outputComponents);