// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package vardecl

// Prerequisites.
import "math"
func f() {}
func g() (x, y int) { return }
var m map[string]int

// Var decls must have a type or an initializer.
var _ int
var _, _ int

var _; /* ERROR "expected type" */
var _, _; /* ERROR "expected type" */

	{"TypeDecl", `type (@T = int)`},

	{"VarDecl", `var @x int`},
	{"VarDecl", `var @x, y, z int`},
	{"VarDecl", `var @x int = 0`},
	{"VarDecl", `var @x, y, z int = 1, 2, 3`},
	{"VarDecl", `var @x = 0`},
	{"VarDecl", `var @x, y, z = 1, 2, 3`},
	{"VarDecl", `var (@x int)`},
	{"VarDecl", `var (@x, y, z int)`},
	{"VarDecl", `var (@x int = 0)`},
	{"VarDecl", `var (@x, y, z int = 1, 2, 3)`},
	{"VarDecl", `var (@x = 0)`},

		case *File:
			// file block starts at the beginning of the file
			return MakePos(n.Pos().Base(), 1, 1)

		// declarations
		// case *ImportDecl:
		// case *ConstDecl:
		// case *TypeDecl:
		// case *VarDecl:
		// case *FuncDecl:

		// expressions
		// case *BadExpr:
		// case *Name:
		// case *BasicLit:
		case *CompositeLit:
			if n.Type != nil {
				m = n.Type
				continue
			}
			return n.Pos()

		varDecls = []*varDecl{}
		useAssemblyRegMap()
	case "memchr", "memcmp":
		varDecls = []*varDecl{{count: 2, typ: i32}}
		useAssemblyRegMap()
	case "cmpbody":
		varDecls = []*varDecl{{count: 2, typ: i64}}
		useAssemblyRegMap()
	case "gcWriteBarrier":
		varDecls = []*varDecl{{count: 5, typ: i64}}
		useAssemblyRegMap()
	case "runtime.gcWriteBarrier1",

// The text is the directive, with the "//" prefix stripped.
// The current pragma is saved at each package, import, const, func, type, or var
// declaration, into the File, ImportDecl, ConstDecl, FuncDecl, TypeDecl, or VarDecl node.
//
// If text is the empty string, the pragma is being returned
// to the handler unused, meaning it appeared before a non-declaration.
// The handler may wish to report an error. In this case, pos is the

		iota      int
		typ       ast.Expr
		init      []ast.Expr
		inherited bool
	}
	varDecl  struct{ spec *ast.ValueSpec }
	typeDecl struct{ spec *ast.TypeSpec }
	funcDecl struct{ decl *ast.FuncDecl }
)

func (d importDecl) node() ast.Node { return d.spec }
func (d constDecl) node() ast.Node  { return d.spec }
func (d varDecl) node() ast.Node    { return d.spec }
func (d typeDecl) node() ast.Node   { return d.spec }

	for stmtIndex, stmt := range stmtList {
		lstmt = nil
	L:
		switch s := stmt.(type) {
		case *DeclStmt:
			for _, d := range s.DeclList {
				if v, ok := d.(*VarDecl); ok {
					recordVarDecl(v.Pos(), v.NameList[0])
					break // the first VarDecl will do
				}
			}

		case *LabeledStmt:
			// declare non-blank label
			if name := s.Label.Value; name != "_" {
				l := ls.declare(b, s)

	switch obj := obj.(type) {
	case *Const:
		check.decl = d // new package-level const decl
		check.constDecl(obj, d.vtyp, d.init, d.inherited)
	case *Var:
		check.decl = d // new package-level var decl
		check.varDecl(obj, d.lhs, d.vtyp, d.init)
	case *TypeName:
		// invalid recursive types are detected via path
		check.typeDecl(obj, d.tdecl, def)
		check.collectMethods(obj) // methods can only be added to top-level types
	case *Func:

		if n.Type != nil {
			w.node(n.Type)
		}
		if n.Values != nil {
			w.node(n.Values)
		}

	case *TypeDecl:
		w.node(n.Name)
		w.fieldList(n.TParamList)
		w.node(n.Type)

	case *VarDecl:
		w.nameList(n.NameList)
		if n.Type != nil {
			w.node(n.Type)
		}
		if n.Values != nil {
			w.node(n.Values)
		}

	case *FuncDecl:
		if n.Recv != nil {
			w.node(n.Recv)
		}

		return false
	}

	var stmtBranches func(syntax.Stmt)
	stmtBranches = func(s syntax.Stmt) {
		switch s := s.(type) {
		case *syntax.DeclStmt:
			for _, d := range s.DeclList {
				if d, _ := d.(*syntax.VarDecl); d != nil {
					recordVarDecl(d.Pos())
				}
			}

		case *syntax.LabeledStmt:
			// declare non-blank label
			if name := s.Label.Value; name != "_" {
				lbl := NewLabel(s.Label.Pos(), check.pkg, name)