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Janus

Welcome

Getting Started

A Practical Guide

Shoring Up the Basics

Views, View Models, and You

From Views to Models

Maps and Models

Client and Server

And the Server, Too

First Principles

Origins and Goals

Rederiving Janus

Varying

From Expressions

Views, Templates, Mutators

Lists

Maps and Models

Requests, Resolvers, References

App and Applications

Resource Management

Further Reading

Attaching Views

View Custom Rendering

Traversal

Cookbook

Bootstrapping an Application

Flyouts

Draggable Objects

Varying

Definition and Instantiation

Varying[T]

@box

Varying[T]

@of

Varying[T]

Data Manipulation

#get

T

#set

void

Value Observation

#react

Observation

Mapping and Transformation

#map

Varying[U]

#flatMap

Varying[U]

#flatten

Varying[T]

#pipe

Varying[U]

Multivalue Processing

@mapAll

Varying[U]

Varying[U]

@lift

(…xs: …V[*] → y: V[U])

@all

UnreducedVarying[*, …]

Resource Management

@managed

Varying[T]

#refCount

Varying[Int]

Reaction Management

#stop

void

Case

Case set definition

@build

{ String : (* → Case) }

Instance Value Extraction

#get

T

#{x}OrElse

T|U

#get{X}

T|Case[*]

#match

Boolean|U?

#toString

String

Mapping and Transformation

#map

Case[U]

#map{X}

Case[U]

Case Type Matching

λmatch

Case[…*] → *

Otherwise[*]

types

.from

{ cases }

.result

{ cases }

.validity

{ cases }

.operation

{ cases }

.traversal

{ cases }

from

from

FromPart[…*, dynamic[T]]

#{x}

FromPart[…*, {x}[T]]

#and

from

#map

FromPart[…*, U]

#flatMap

FromPart[…*, U]

#get

FromPart[…*, U]

#attribute

FromPart[…*, Attribute]

#pipe

FromPart[…*, U]

#asVarying

FromPart[…*, Varying[T]]

Chain Finalization

.all

From[…*]

#map

From[U]

#flatMap

From[U]

#point

UnreducedVarying[…*]

Custom Chaining

@build

from

Base

Events

#on

self

#off

self

#emit

Boolean

#listeners

Array[(…* → void)]

#removeAllListeners

self

#listenTo

self

self

Varying Observation

#reactTo

Observation

Lifecycle Management

self

#destroy

void

@managed

(void → Base)

#tap

self

Extending Base (Overrides)

Base

#_destroy

void

List

Creation

List|List[T]

List

Value Manipulation

#add

void

#set

void

#remove

T?

#removeAt

T?

#removeAll

Array

#move

T?

#moveAt

T

Value Retrieval and Observation

#at

Varying[*?]

#at_

*?

.length

Varying[Int]

.length_

Int

#empty

Varying[Boolean]

#empty_

Boolean

#nonEmpty

Varying[Boolean]

#nonEmpty_

Boolean

.list

Array

Mapping and Transformation

#map

List[U]

#flatMap

List[U]

#mapPairs

List[U]

List[U]

#filter

List[T]

#take

List[T]

#flatten

List[*]

#concat

List[*]

#uniq

List[*]

#serialize

[*]

Fold-like Operations

#includes

Varying[Boolean]

#indexOf

Varying[Int]

#any

Varying[Boolean]

#min

Varying[Number]

#max

Varying[Number]

#sum

Varying[Number]

#enumerate

List[Int]

Array[Int]

Change Detection

#diff

Varying[Boolean]

Set

Creation

Set|Set[T]

Set

Value Manipulation

#add

void

#remove

T?

Value Retrieval and Observation

#includes

Varying[Boolean]

#includes_

Boolean

.length

Varying[Int]

.length_

Int

Mapping and Transformation

#map

List[U]

#flatMap

List[U]

#filter

List[T]

#flatten

Set[*]

#uniq

this

#serialize

[*]

Fold-like Operations

#any

Varying[Boolean]

#min

Varying[Number]

#max

Varying[Number]

#sum

Varying[Number]

#enumerate

this

Array[*]

Map

Creation

Map

Map

Value Manipulation

#set

void|(value: * → void)

#unset

void

Value Retrieval and Observation

#get

Varying[*]

#get_

*|null

#shadow

Map|T

#with

Map

#revert

void

#original

Map

Mapping and Transformation

#mapPairs

Map

Map

#serialize

{*}

#enumerate

Array[String]

#keys

Set[String]

#enumerate

Array[String]

#keys_

Array[String]

#values

List[*]

#values_

List[*]

.length

Varying[Int]

.length_

Int

Change Detection

#diff

Varying[Boolean]

#modified

Varying[Boolean]

Traversal

Performing Traversal

λnatural

Map|List

λnatural_

Object|Array

λlist

List

λlist_

Array

Default Implementations

{ map }

::diff

{ recurse, map, reduce }

Model

Building a Model

@build

@Model

Schema → void

λbind

Schema → void

λinitial

Schema → void

Schema → void

λvalidate

Schema → void

Trait

Builder

Creation

Model

Model

Value Manipulation

#set

void|(value: * → void)

#unset

void

#get

*|null

#get_

*|null

Schema Information

#attribute

Attribute?

Array[Attribute]

Binding and Context

#pointer

types.from → Varying

Model Validation

List[types.validity]

#errors

List[*]

#valid

Varying[Boolean]

#shadow

Model|T

#with

Map

#revert

void

#original

Model

Mapping and Transformation

#mapPairs

Model

Model

#serialize

{*}

#enumerate

Set[String]

#keys

Set[String]

Array[String]

#keys_

Array[String]

#values

List[*]

#values_

Array[*]

.length

Varying[Int]

.length_

Int

Change Detection

#diff

Varying[Boolean*]

#modified

Varying[Boolean*]

Extending Model (Overrides)

#_preinitialize

void

void

Attribute

Attribute Base Class

Attribute

#getValue

Varying[*]

#getValue_

*|null

#setValue

void

void

#serialize

*|null

.transient

Boolean

*

#default

*?

Boolean

.model

Model

.key

Model

#_values

Binding[Listlike[T]]

#nullable

Boolean

Number Attribute

Boolean Attribute

Model Attribute

@Model

@of

@ListAttribute

@listClass

@List

@of

@ListAttribute

Reference Attribute

#request

Binding[Request]

@to

@ReferenceAttribute

Boolean

void

Request

Creation

Request

.type

types.operation

#signature

String?

.cacheable

Boolean

#expires

Number?

Resolver

Combining Resolvers

λoneOf

Resolver

Basic Resolvers

Resolver

λfromDom

Resolver

Caching

λcaching

Resolver

Cache

View

Creation

View

Rendering and Context

#artifact

*

#pointer

types.from → Varying[*]

Navigation

#parent

Varying[View?]

#parent_

View?

#closest

Varying[View?]

#closest_

View?

#into

Varying[View?]

#into_

View?

#intoAll

List[View]

#intoAll_

Array[View]

Extending View (Overrides)

@viewModelClass

@Model?

#_render

*

DomView

Building a DomView

@build

@DomView

λfind

Template

find

λtemplate

Template

Mutators

.attr

Template

.prop

Template

.classed

Template

Template

.css

Template

.text

Template

.html

Template

.render

Template

.on

Template

Creation

DomView

Rendering and Events

#artifact

$Node

#pointer

types.from → Varying[*]

#attach

$Node

void

Navigation

#parent

Varying[View?]

#parent_

View?

#closest

Varying[View?]

#closest_

View?

#into

Varying[View?]

#into_

View?

#intoAll

List[View]

#intoAll_

Array[View]

Extending DomView (Overrides)

void

#_render

$Node

#_attach

void

@viewModelClass

@Model?

App

Creation

App

Application Views

.views

Library

#view

View?

Application Resolvers

.resolvers

Library

#resolve

Varying[types.result]?

Extending App (Overrides)

#resolver

Resolver

Library

Creation

Library

Catalog Management

#register

void

#get

*?

Manifest

Creation

Manifest

@run

Manifest

.result

Varying[types.result]

#then

Promise

.requests

List[RequestInfo]

.view

*

.model

Model

Community

Resources

Contributor Guide

Code of Conduct

Resources§

Currently, you can find others using Janus in two places.

You can check the GitHub repository for issue tickets and pull requests. If you have suggestions or ideas, please submit a pull request, or file an issue ticket.

If you have questions about using Janus, you can find us on Discord.