// 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 types

import (

"fmt"

"go/ast"

"go/parser"

"go/token"

)

// Eval returns the type and, if constant, the value for the

// expression expr, evaluated at position pos of package pkg,

// which must have been derived from type-checking an AST with

// complete position information relative to the provided file

// set.

//

// The meaning of the parameters fset, pkg, and pos is the

// same as in [CheckExpr]. An error is returned if expr cannot

// be parsed successfully, or the resulting expr AST cannot be

// type-checked.

func Eval(fset *token.FileSet, pkg *Package, pos token.Pos, expr string) (_ TypeAndValue, err error) {

}

// CheckExpr type checks the expression expr as if it had appeared at position

// pos of package pkg. [Type] information about the expression is recorded in

// info. The expression may be an identifier denoting an uninstantiated generic

// function or type.

//

// If pkg == nil, the [Universe] scope is used and the provided

// position pos is ignored. If pkg != nil, and pos is invalid,

// the package scope is used. Otherwise, pos must belong to the

// package.

//

// An error is returned if pos is not within the package or

// if the node cannot be type-checked.

//

// Note: [Eval] and CheckExpr should not be used instead of running Check

// to compute types and values, but in addition to Check, as these

// functions ignore the context in which an expression is used (e.g., an

// assignment). Thus, top-level untyped constants will return an

// untyped type rather than the respective context-specific type.

func CheckExpr(fset *token.FileSet, pkg *Package, pos token.Pos, expr ast.Expr, info *Info) (err error) {

}