engine

Documentation

Index

• Variables
• type Engine
  • func Start() *Engine
  • func (e *Engine) Hangup()
  • func (e *Engine) Observe(expr rel.Expr, onupdate func(rel.Value) error, onclose func(error)) func()
  • func (e *Engine) Stop()
  • func (e *Engine) Update(expr rel.Expr) error

Variables

var (
	// Root holds the variable name used for the database variable.
	Root = "$"
)

Types

type Engine

type Engine struct {
	// contains filtered or unexported fields
}

Engine holds a database variable, allowing updates and publishing changes.

func Start

func Start() *Engine

Start starts a new Engine.

func (*Engine) Hangup

func (e *Engine) Hangup()

Hangup hangs up on all observers.

func (*Engine) Observe

func (e *Engine) Observe(
	expr rel.Expr,
	onupdate func(rel.Value) error,
	onclose func(error),
) func()

Observe registers and returns an Observation on the given expression.

func (*Engine) Stop

func (e *Engine) Stop()

Stop stops the engine.

func (*Engine) Update

func (e *Engine) Update(expr rel.Expr) error

Update updates the database variable to equal the given expression.