style changes.

- method names can't start with "Get", enforced by the style tool.
- document our preference for return-by-reference, given the new design.

DESIGN.md

@@ -74,6 +74,11 @@ improvement in the following regards.
 *   Identifier naming generally makes use of CamelCasing. Leading
     upper/lowercase letter dictates private/public to package, as defined by
     the Go programming language.
+*   Getter method names should *not* start with "Get". See
+    http://golang.org/doc/effective_go.html#Getters
+*   Functions and methods should preferably return objects by reference
+    (pointer) and callers can change them freely without fear of
+    synchronization issues, thanks to our clear channels-based design.
 
 To ease the above, there are three make targets:
 

src/util/style/style.go

@@ -21,15 +21,17 @@ func main() {
 
 	v := NewNodeChecker(fset)
 	v.InterfaceName = regexp.MustCompile("I[A-Z][A-Za-z]+")
+	v.InvalidFuncName = regexp.MustCompile("^Get") // can't do negative match in Go's regexp?
 
 	for _, pkg := range pkgMap {
 		ast.Walk(v, pkg)
 	}
 }
 
 type NodeChecker struct {
-	fset          *token.FileSet
-	InterfaceName *regexp.Regexp
+	fset            *token.FileSet
+	InterfaceName   *regexp.Regexp
+	InvalidFuncName *regexp.Regexp
 }
 
 func NewNodeChecker(fset *token.FileSet) *NodeChecker {
@@ -42,6 +44,10 @@ func (v *NodeChecker) Visit(node ast.Node) (w ast.Visitor) {
 	switch n := node.(type) {
 	case *ast.TypeSpec:
 		v.checkTypeName(n)
+	case *ast.FuncDecl:
+		if n.Recv != nil { // is a method.
+			v.checkFunc(n)
+		}
 	}
 	return v
 }
@@ -62,6 +68,12 @@ func (v *NodeChecker) report(pos token.Pos, format string, args ...interface{})
 		allArgs...)
 }
 
+func (v *NodeChecker) checkFunc(f *ast.FuncDecl) {
+	if v.InvalidFuncName.MatchString(f.Name.String()) {
+		v.report(f.Name.NamePos, "Bad name for method %q\n", f.Name)
+	}
+}
+
 func (v *NodeChecker) checkTypeName(typeSpec *ast.TypeSpec) {
 	name := typeSpec.Name.Name
 	switch t := typeSpec.Type.(type) {