}

// litStmts returns all statements from the function body of a function
// literal.
//
// If fun is not a function literal, it returns nil.
func litStmts(fun ast.Expr) []ast.Stmt {
	lit, _ := fun.(*ast.FuncLit)
	if lit == nil {
		return nil
	}
	return lit.Body.List
}

// goInvoke returns a function expression that would be called asynchronously

	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
	case *ast.GoStmt:
		return 1 << nGoStmt
	case *ast.Ident:
		return 1 << nIdent

		}
		if n.Type.Results != nil {
			children = append(children, n.Type.Results)
		}
		if n.Body != nil {
			children = append(children, n.Body)
		}

	case *ast.FuncLit:
		// nop

	case *ast.FuncType:
		if n.Func != 0 {
			children = append(children,
				tok(n.Func, len("func")))
		}

	case *ast.GenDecl:
		children = append(children,

	case *CompositeLit:
		if n.Type != nil {
			w.node(n.Type)
		}
		w.exprList(n.ElemList)

	case *KeyValueExpr:
		w.node(n.Key)
		w.node(n.Value)

	case *FuncLit:
		w.node(n.Type)
		w.node(n.Body)

	case *ParenExpr:
		w.node(n.X)

	case *SelectorExpr:
		w.node(n.X)
		w.node(n.Sel)

	case *IndexExpr:
		w.node(n.X)
		w.node(n.Index)

		}

	case *FieldList:
		walkList(v, n.List)

	// Expressions
	case *BadExpr, *Ident, *BasicLit:
		// nothing to do

	case *Ellipsis:
		if n.Elt != nil {
			Walk(v, n.Elt)
		}

	case *FuncLit:
		Walk(v, n.Type)
		Walk(v, n.Body)

	case *CompositeLit:
		if n.Type != nil {
			Walk(v, n.Type)
		}
		walkList(v, n.Elts)

	case *ParenExpr:
		Walk(v, n.X)

	case *SelectorExpr:

		NKeys    int // number of elements with keys
		Rbrace   Pos
		expr
	}

	// Key: Value
	KeyValueExpr struct {
		Key, Value Expr
		expr
	}

	// func Type { Body }
	FuncLit struct {
		Type *FuncType
		Body *BlockStmt
		expr
	}

	// (X)
	ParenExpr struct {
		X Expr
		expr
	}

	// X.Sel
	SelectorExpr struct {
		X   Expr
		Sel *Name
		expr

	switch t := x.typ.(type) {
	case *Alias, *Named:
		if isGeneric(t) {
			what = "type"
		}
	case *Signature:
		if t.tparams != nil {
			if enableReverseTypeInference && T != nil {
				check.funcInst(T, x.Pos(), x, nil, true)
				return
			}
			what = "function"
		}
	}
	if what != "" {
		check.errorf(x.expr, WrongTypeArgCount, "cannot use generic %s %s without instantiation", what, x.expr)

	{"BasicLit", "@`abc`"},

	{"CompositeLit", `@{}`},
	{"CompositeLit", `T@{}`},
	{"CompositeLit", `struct{x, y int}@{}`},

	{"KeyValueExpr", `"foo"@: true`},
	{"KeyValueExpr", `"a"@: b`},

	{"FuncLit", `@func (){}`},
	{"ParenExpr", `@(x)`},
	{"SelectorExpr", `a@.b`},
	{"IndexExpr", `a@[i]`},

	{"SliceExpr", `a@[:]`},
	{"SliceExpr", `a@[i:]`},
	{"SliceExpr", `a@[:j]`},
	{"SliceExpr", `a@[i:j]`},

	switch t := x.typ.(type) {
	case *Alias, *Named:
		if isGeneric(t) {
			what = "type"
		}
	case *Signature:
		if t.tparams != nil {
			if enableReverseTypeInference && T != nil {
				check.funcInst(T, x.Pos(), x, nil, true)
				return
			}
			what = "function"
		}
	}
	if what != "" {
		check.errorf(x.expr, WrongTypeArgCount, "cannot use generic %s %s without instantiation", what, x.expr)

	// the curfn stack.
	var curfn []*ast.FuncType

	before := func(n any) {
		// push function type on stack
		switch n := n.(type) {
		case *ast.FuncDecl:
			curfn = append(curfn, n.Type)
		case *ast.FuncLit:
			curfn = append(curfn, n.Type)
		}
	}

	// After is the real type checker.
	after := func(n any) {
		if n == nil {
			return
		}