Merge pull request #4498

2887bff Update coding style and add .clang-format (Pieter Wuille)

doc/coding.md

@@ -1,29 +1,17 @@
 Coding
 ====================
 
-Please be consistent with the existing coding style.
-
-Block style:
-```c++
-    bool Function(char* psz, int n)
-    {
-        // Comment summarising what this section of code does
-        for (int i = 0; i < n; i++)
-        {
-            // When something fails, return early
-            if (!Something())
-                return false;
-            ...
-        }
-
-        // Success return is usually at the end
-        return true;
-    }
-```
-- ANSI/Allman block style
-- 4 space indenting, no tabs
-- No extra spaces inside parenthesis; please don't do ( this )
-- No space after function names, one space after if, for and while
+Various coding styles have been used during the history of the codebase,
+and the result is not very consistent. However, we're now trying to converge to
+a single style, so please use it in new code. Old code will be converted
+gradually.
+- Basic rules specified in src/.clang-format. Use a recent clang-format-3.5 to format automatically.
+  - Braces on new lines for namespaces, classes, functions, methods.
+  - Braces on the same line for everything else.
+  - 4 space indentation (no tabs) for every block except namespaces.
+  - No indentation for public/protected/private or for namespaces.
+  - No extra spaces inside parenthesis; don't do ( this )
+  - No space after function names; one space after if, for and while.
 - Includes need to be ordered alphabetically, separate own and foreign headers with a new-line (example key.cpp):
 ```c++
 #include "key.h"
@@ -38,31 +26,29 @@ Block style:
 class CAlpha;
 class CBeta;
 ```
-- When using namespace keyword use the following form:
+
+Block style example:
 ```c++
-namespace Foo {
+namespace foo
+{
+class Class
+{
+    bool Function(char* psz, int n)
+    {
+        // Comment summarising what this section of code does
+        for (int i = 0; i < n; i++) {
+            // When something fails, return early
+            if (!Something())
+                return false;
+            ...
+        }
 
-...
-
-} // Foo
+        // Success return is usually at the end
+        return true;
+    }
+}
+}
 ```
-Variable names begin with the type in lowercase, like nSomeVariable.
-Please don't put the first word of the variable name in lowercase like
-someVariable.
-
-Common types:
-
-    n       integer number: short, unsigned short, int, unsigned int, int64, uint64, sometimes char if used as a number
-    d       double, float
-    f       flag
-    hash    uint256
-    p       pointer or array, one p for each level of indirection
-    psz     pointer to null terminated string
-    str     string object
-    v       vector or similar list objects
-    map     map or multimap
-    set     set or multiset
-    bn      CBigNum
 
 Doxygen comments
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