ch7_eval

package

v0.0.0-...-5afa7de Latest Latest Go to latest Published: May 18, 2020 License: Apache-2.0 Imports: 5 Imported by: 0

Details

Valid go.mod file
Redistributable license
Tagged version
Stable version
Learn more about best practices

Repository

github.com/wangyoucao577/golang

Links

Open Source Insights

Documentation ¶

Index ¶

type Env
type Expr
- func Parse(input string) (_ Expr, err error)
type Var
- func (v Var) Check(vars map[Var]bool) error
- func (v Var) Eval(env Env) float64

Constants ¶

This section is empty.

Variables ¶

This section is empty.

Functions ¶

This section is empty.

Types ¶

type Env ¶

type Env map[Var]float64

type Expr ¶

type Expr interface {
	Eval(env Env) float64

	// Check reports errors in this Expr and adds its Vars to the set.
	Check(vars map[Var]bool) error
}

An Expr is an arithmetic expression.

func Parse ¶

func Parse(input string) (_ Expr, err error)

Parse parses the input string as an arithmetic expression.

expr = num                         a literal number, e.g., 3.14159
     | id                          a variable name, e.g., x
     | id '(' expr ',' ... ')'     a function call
     | '-' expr                    a unary operator (+-)
     | expr '+' expr               a binary operator (+-*/)

type Var ¶

type Var string

A Var identifies a variable, e.g., x

func (Var) Check ¶

func (v Var) Check(vars map[Var]bool) error

func (Var) Eval ¶

func (v Var) Eval(env Env) float64

Source Files ¶

View all Source files

?	: This menu
/	: Search site
f or F	: Jump to
y or Y	: Canonical URL