Merge pull request #6875 from ethereum/docs-style-fixes-values

[DOCS] Bring value types code examples inline with style guide

docs/types/value-types.rst

@@ -624,10 +624,12 @@ Example that shows how to use the members::
 
     pragma solidity >=0.4.16 <0.7.0;
 
+
     contract Example {
         function f() public payable returns (bytes4) {
             return this.f.selector;
         }
+
         function g() public {
             this.f.gas(10).value(800)();
         }
@@ -637,6 +639,7 @@ Example that shows how to use internal function types::
 
     pragma solidity >=0.4.16 <0.7.0;
 
+
     library ArrayUtils {
         // internal functions can be used in internal library functions because
         // they will be part of the same code context
@@ -650,6 +653,7 @@ Example that shows how to use internal function types::
                 r[i] = f(self[i]);
             }
         }
+
         function reduce(
             uint[] memory self,
             function (uint, uint) pure returns (uint) f
@@ -663,6 +667,7 @@ Example that shows how to use internal function types::
                 r = f(r, self[i]);
             }
         }
+
         function range(uint length) internal pure returns (uint[] memory r) {
             r = new uint[](length);
             for (uint i = 0; i < r.length; i++) {
@@ -671,14 +676,18 @@ Example that shows how to use internal function types::
         }
     }
 
+
     contract Pyramid {
         using ArrayUtils for *;
+
         function pyramid(uint l) public pure returns (uint) {
             return ArrayUtils.range(l).map(square).reduce(sum);
         }
+
         function square(uint x) internal pure returns (uint) {
             return x * x;
         }
+
         function sum(uint x, uint y) internal pure returns (uint) {
             return x + y;
         }
@@ -688,32 +697,39 @@ Another example that uses external function types::
 
     pragma solidity >=0.4.22 <0.7.0;
 
+
     contract Oracle {
         struct Request {
             bytes data;
             function(uint) external callback;
         }
-      Request[] requests;
+
+        Request[] private requests;
         event NewRequest(uint);
+
         function query(bytes memory data, function(uint) external callback) public {
             requests.push(Request(data, callback));
             emit NewRequest(requests.length - 1);
         }
+
         function reply(uint requestID, uint response) public {
             // Here goes the check that the reply comes from a trusted source
             requests[requestID].callback(response);
         }
     }
 
+
     contract OracleUser {
-      Oracle constant oracle = Oracle(0x1234567); // known contract
-      uint exchangeRate;
+        Oracle constant private ORACLE_CONST = Oracle(0x1234567); // known contract
+        uint private exchangeRate;
+
         function buySomething() public {
-        oracle.query("USD", this.oracleResponse);
+            ORACLE_CONST.query("USD", this.oracleResponse);
         }
+
         function oracleResponse(uint response) public {
             require(
-            msg.sender == address(oracle),
+                msg.sender == address(ORACLE_CONST),
                 "Only oracle can call this."
             );
             exchangeRate = response;