}

func run(pass *analysis.Pass) (interface{}, error) {
	inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)

	nodeFilter := []ast.Node{
		(*ast.File)(nil),
		(*ast.RangeStmt)(nil),
		(*ast.ForStmt)(nil),
	}
	inspect.Nodes(nodeFilter, func(n ast.Node, push bool) bool {
		if !push {
			// inspect.Nodes is slightly suboptimal as we only use push=true.
			return true
		}

	}
	return r.useObj(r.nextVar)
}

// forRangeFunc checks whether n is a range-over-func.
// If so, it returns n.(*syntax.ForStmt), true.
// Otherwise it returns nil, false.
func forRangeFunc(n syntax.Node) (*syntax.ForStmt, bool) {
	nfor, ok := n.(*syntax.ForStmt)
	if !ok {
		return nil, false
	}
	nrange, ok := nfor.Init.(*syntax.RangeClause)
	if !ok {
		return nil, false
	}

		d.labels[x.Label.Name] = x.Stmt
		d.findLabels(x.Stmt)

	// These cases are all the same, but the x.Body only works
	// when the specific type of x is known, so the cases cannot
	// be merged.
	case *ast.ForStmt:
		outer := d.breakTarget
		d.breakTarget = x
		d.findLabels(x.Body)
		d.breakTarget = outer

	case *ast.RangeStmt:
		outer := d.breakTarget
		d.breakTarget = x
		d.findLabels(x.Body)

		// Target is the continuation of the control flow after executing
		// the branch; it is computed by the parser if CheckBranches is set.
		// Target is a *LabeledStmt for gotos, and a *SwitchStmt, *SelectStmt,
		// or *ForStmt for breaks and continues, depending on the context of
		// the branch. Target is not set for fallthroughs.
		Target Stmt
		stmt
	}

	CallStmt struct {
		Tok     token // Go or Defer
		Call    Expr

	case *ast.ExprStmt:
		return 1 << nExprStmt
	case *ast.Field:
		return 1 << nField
	case *ast.FieldList:
		return 1 << nFieldList
	case *ast.File:
		return 1 << nFile
	case *ast.ForStmt:
		return 1 << nForStmt
	case *ast.FuncDecl:
		return 1 << nFuncDecl
	case *ast.FuncLit:
		return 1 << nFuncLit
	case *ast.FuncType:
		return 1 << nFuncType
	case *ast.GenDecl:
		return 1 << nGenDecl

	}

	// A SelectStmt node represents a select statement.
	SelectStmt struct {
		Select token.Pos  // position of "select" keyword
		Body   *BlockStmt // CommClauses only
	}

	// A ForStmt represents a for statement.
	ForStmt struct {
		For  token.Pos // position of "for" keyword
		Init Stmt      // initialization statement; or nil
		Cond Expr      // condition; or nil
		Post Stmt      // post iteration statement; or nil

			tok(n.Opening, len("(")), // or len("[")
			tok(n.Closing, len(")"))) // or len("]")

	case *ast.File:
		// TODO test: Doc
		children = append(children,
			tok(n.Package, len("package")))

	case *ast.ForStmt:
		children = append(children,
			tok(n.For, len("for")))

	case *ast.FuncDecl:
		// TODO(adonovan): FuncDecl.Comment?

		// Uniquely, FuncDecl breaks the invariant that

			w.node(n.Results)
		}

	case *IfStmt:
		if n.Init != nil {
			w.node(n.Init)
		}
		w.node(n.Cond)
		w.node(n.Then)
		if n.Else != nil {
			w.node(n.Else)
		}

	case *ForStmt:
		if n.Init != nil {
			w.node(n.Init)
		}
		if n.Cond != nil {
			w.node(n.Cond)
		}
		if n.Post != nil {
			w.node(n.Post)
		}
		w.node(n.Body)

	case *SwitchStmt:

	{name: "for1", format: "package main; func main() { «for x { «» }» }", scope: true, scopeMultiplier: 2},                          // Scopes: ForStmt, BlockStmt
	{name: "for3", format: "package main; func main() { «for f(); g(); h() { «» }» }", scope: true, scopeMultiplier: 2},              // Scopes: ForStmt, BlockStmt

		}
		Walk(v, n.Assign)
		Walk(v, n.Body)

	case *CommClause:
		if n.Comm != nil {
			Walk(v, n.Comm)
		}
		walkList(v, n.Body)

	case *SelectStmt:
		Walk(v, n.Body)

	case *ForStmt:
		if n.Init != nil {
			Walk(v, n.Init)
		}
		if n.Cond != nil {
			Walk(v, n.Cond)
		}
		if n.Post != nil {
			Walk(v, n.Post)
		}
		Walk(v, n.Body)

	case *RangeStmt: