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<!DOCTYPE html>  <html lang="en"> <head> <meta charset="utf-8"> <title>CanJS - can-view-scope</title> <meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1, user-scalable=no"> <link rel="stylesheet" type="text/css" href="./static/bundles/bit-docs-site/static.css"> <link rel="shortcut icon" sizes="16x16 24x24 32x32 48x48 64x64" href="/docs/images/canjs_favicon.ico"> <link rel="apple-touch-icon" sizes="57x57" href="../docs/images/canjs_favicon_57x57.png"> <link rel="apple-touch-icon-precomposed" sizes="57x57" href="../docs/images/canjs_favicon_57x57.png"> <link rel="apple-touch-icon" sizes="72x72" href="../docs/images/canjs_favicon_72x72.png"> <link rel="apple-touch-icon" sizes="114x114" href="../docs/images/canjs_favicon_114x114.png"> <link rel="apple-touch-icon" sizes="120x120" href="../docs/images/canjs_favicon_128x128.png"> <link rel="apple-touch-icon" sizes="144x144" href="../docs/images/canjs_favicon_144x144.png"> <link rel="apple-touch-icon" sizes="152x152" href="../docs/images/canjs_favicon_152x152.png"> <meta content="yes" name="apple-mobile-web-app-capable"> <meta name="apple-mobile-web-app-status-bar-style" content="white-translucent"> <script> (function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){ (i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o), m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m) })(window,document,'script','https://www.google-analytics.com/analytics.js','ga'); ga('create', 'UA-2302003-11', 'auto'); ga('send', 'pageview'); </script> </head> <body> <input type="checkbox" id="nav-trigger" class="nav-trigger"/> <label for="nav-trigger">Menu</label> <div id="everything"> <div id="left" class="column"> <div class="top-left"> <div class="brand"> <div class="logo"> <a href="../index.html" alt="CanJS"></a> <div class="dropdown project-dropdown"> <a href="https://donejs.com/">DoneJS</a> <a href="http://stealjs.com/">StealJS</a> <a href="http://jquerypp.com/">jQuery ++</a> <a href="https://funcunit.com/">FuncUnit</a> <a href="http://documentjs.com/">DocumentJS</a> </div> </div> <div class="version"> <div class="version-number"> 3.0.0 </div> <div class="dropdown version-dropdown"> <a href="https://v2.canjs.com">2.3.27</a> </div> </div> </div> <div class="search-bar"> <p>   </p> </div> </div> <div class="bottom-left"> <div class="social-side-container"> <ul class="social-side"> <li> <a class="header-mobile github" href="https://github.com/canjs/canjs" target="_blank"><img class="social-icon-small" src="../docs/images/github.png">Github</a> </li> <li> <a class="header-mobile twitter" href="https://twitter.com/canjs" target="_blank"><img class="social-icon-small" src="../docs/images/twitter.png">Twitter</a> </li> </ul> <ul class="social-side"> <li> <a class="header-mobile" href="https://gitter.im/canjs/canjs" target="_blank">Chat</a> </li> <li> <a class="header-mobile" href="http://forums.donejs.com/c/canjs" target="_blank">Forum</a> </li> </ul> </div> <ul> <li class=" "> <a class="page" href="guides.html" title="Welcome to CanJS! 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If {{#items}} changes the DOM by adding more <labels>, {{#if}} needs to know about the <labels> to remove them if {{#if}} is re-rendered. {{#if}} would be re-rendered, for example, if all items were removed."> can-view-nodelist </a> </li> <li class=" "> <a class="module" href="can-view-parser.html" title="Parse HTML and mustache tokens."> can-view-parser </a> </li> <li class="current parent expanded"> <a class="module" href="can-view-scope.html" title="Create a lookup node for keys."> can-view-scope </a> <ul> <li> <span>types</span> <ul> <li class=" "> <a class="typedef" href="can-view-scope/Meta.html" title=""> Meta </a> </li> </ul> </li> <li> <span>static</span> <ul> <li class=" "> <a class="function" href="can-view-scope.Options.html" title=""> Options </a> </li> </ul> </li> <li> <span>prototype</span> <ul> <li class=" "> <a class="function" href="can-view-scope.prototype.add.html" title=""> add </a> </li> <li class=" "> <a class="function" href="can-view-scope.prototype.compute.html" title=""> compute </a> </li> <li class=" "> <a class="function" href="can-view-scope.prototype.get.html" title=""> get </a> </li> <li class=" "> <a class="function" href="can-view-scope.prototype.peek.html" title="Read a value from the scope without being observable."> peek </a> </li> <li class=" "> <a class="function" href="can-view-scope.prototype.set.html" title=""> set </a> </li> </ul> </li> </ul> </li> <li class=" "> <a class="module" href="can-view-target.html" title=""> can-view-target </a> </li> </ul> </li> <li class=" "> <a class="page" href="can-legacy.html" title="Former libraries that we still accept patches for, but are not under active development."> Legacy </a> </li> </ul> </div> </div> <div id="right" class="column"> <div class="top-right"> <div class="top-right-top"> <ul class="top-right-bitovi"> <li class="dropdown"> <a href="http://bitovi.com" class="bitovi icon-bits">Bitovi</a> <ul class="dropdown-menu"> <li><a href="http://bitovi.com">Bitovi.com</a></li> <li><a href="http://bitovi.com/blog/">Blog</a></li> <li><a href="http://bitovi.com/consulting/">Consulting</a></li> <li><a href="http://bitovi.com/training/">Training</a></li> <li><a href="http://bitovi.com/open-source/">Open Source</a></li> </ul> </li> </ul> <div class="brand"> <div class="logo"> <a href="../index.html" alt="CanJS"></a> </div> </div> <ul class="top-right-links"> <li> <a href="https://gitter.im/canjs/canjs">Chat</a> </li> <li> <a href="http://forums.donejs.com/c/canjs">Forum</a> </li> <li> <a class="github-button nav-social" href="https://github.com/canjs/canjs" data-count-href="/canjs/canjs/stargazers" data-count-api="/repos/canjs/canjs#stargazers_count">Star</a> </li> <li> <a href="https://twitter.com/canjs" class="twitter-follow-button nav-social" data-show-count="true" data-show-screen-name="false">Follow @canjs</a><script async src="//platform.twitter.com/widgets.js" charset="utf-8"></script> </li> </ul> </div> <div class="breadcrumb"> <li><a href="../index.html">CanJS</a></li> / <li><a href="can-infrastructure.html">Infrastructure</a></li> / <li><a href="can-view-scope.html">can-view-scope</a></li> <li class="breadcrumb-dropdown">/ <a> On this page</a> <ul class="on-this-page"></ul> </li> <div class="nav-toggle" title="Back to top"></div> </div> </div> <div class="bottom-right"> <article> <section class="title"> <div class="page-type"> <h1>can-view-scope</h1> <div>module</div> </div> <section class="description"> <p>Create a lookup node for [can-mustache.key keys].</p> </section> </section> <section class="on-this-page-table"> </section> <section class="title-footer"> <ul class="title-social"> <li> <a class="npm-button" href="https://www.npmjs.com/package/can-view-scope"> <img src="https://img.shields.io/badge/npm%20package-3.1.0-brightgreen.svg" alt="npm package badge" /> </a> </li> <li> <a class="github-button nav-social" href="https://github.com/canjs/can-view-scope" data-count-href="/canjs/can-view-scope/stargazers" data-count-api="/repos/canjs/can-view-scope#stargazers_count">Star</a> </li> </ul> <ul class="title-links">  <li><a href="//github.com/canjs/can-view-scope/tree/v3.1.0/docs/can-view-scope.md">source</a></li>   </ul> </section> <div class="signature"> <h2 class="signature-title"> <code>new Scope(context, [parent], [meta] )</code> </h2> <div class="parameters"> <h3 class="parameters-title">Parameters</h3> <ol> <li><b>context</b> <code>{*}</code>: <p>A value that represents the current context. This is often an object or observable and is the first place a <code>key</code> is looked up.</p> </li> <li><b>parent</b> <code>{<a href="can-view-scope.html" title="Create a lookup node for keys.">can-view-scope</a>}</code>: <p>The parent scope. If a <code>key</code> value is not found in the current scope, it will then look in the parent scope.</p> </li> <li><b>meta</b> <code>{<a href="can-view-scope/Meta.html" title="">Meta</a>}</code>: <p>A configuration object that can specify special behavior of the context.</p> </li> </ol> </div> <div class="returns"> <h3 class="returns-title">Returns</h3> <p> <code>{<a href="can-view-scope.html" title="Create a lookup node for keys.">can-view-scope</a>}</code>: <p>Returns a scope instance.</p> </p> </div> </div> <section class="body"> <h2>Use</h2> <p>A <a href="can-view-scope.html" title="Create a lookup node for keys.">can-view-scope</a> represents a lookup context and parent contexts that can be used to lookup a <a href="can-stache.key.html" title="A named reference to a value in the scope or helper scope in a template.">key</a> value.</p> <p>If no parent scope is provided, only the scope's context will be explored for values. For example:</p> <pre><code>var data = {name: {first: "Justin"}}, scope = new Scope(data); scope.get("name.first") //-> "Justin" scope.get("length") //-> undefined </code></pre> <p>However, if a <code>parent</code> scope is provided, key values will be searched in the parent's context after the initial context is explored. For example:</p> <pre><code>var list = [{name: "Justin"},{name: "Brian"}], justin = list[0]; var listScope = new Scope(list), curScope = new Scope(justin, listScope) curScope.get("name") //-> "Justin" curScope.get("length") //-> 2 </code></pre> <p>Use <a href="can-view-scope.prototype.add.html" title="">add</a> to easily create a new scope from a parent scope like:</p> <pre><code>var list = [{name: "Justin"},{name: "Brian"}], justin = list[0]; var curScope = new Scope(list).add(justin); curScope.get("name") //-> "Justin" curScope.get("length") //-> 2 </code></pre> </section> <script type="text/javascript"> var docObject = {"src":{"path":"node_modules/can-view-scope/docs/can-view-scope.md"},"description":"Create a lookup node for [can-mustache.key keys]. \n\n\n","type":"module","title":"","types":[{"type":"function","returns":{"types":[{"type":"undefined"}]},"params":[]}],"name":"can-view-scope","parent":"can-infrastructure","inherits":"can","test":"can/view/scope/test.html","package":{"_args":[[{"raw":"can-view-scope@3.1.0","scope":null,"escapedName":"can-view-scope","name":"can-view-scope","rawSpec":"3.1.0","spec":"3.1.0","type":"version"},"/Users/kevin/dev/canjs"]],"_from":"can-view-scope@3.1.0","_id":"can-view-scope@3.1.0","_inCache":true,"_location":"/can-view-scope","_nodeVersion":"6.9.1","_npmOperationalInternal":{"host":"packages-12-west.internal.npmjs.com","tmp":"tmp/can-view-scope-3.1.0.tgz_1479318149792_0.18891599983908236"},"_npmUser":{"name":"phillipskevin","email":"kphillips86@gmail.com"},"_npmVersion":"3.10.8","_phantomChildren":{},"_requested":{"raw":"can-view-scope@3.1.0","scope":null,"escapedName":"can-view-scope","name":"can-view-scope","rawSpec":"3.1.0","spec":"3.1.0","type":"version"},"_requiredBy":["#USER","/","/can-component","/can-stache","/can-stache-bindings","/can-view-href"],"_resolved":"https://registry.npmjs.org/can-view-scope/-/can-view-scope-3.1.0.tgz","_shasum":"1bcd00deba0c96531dfc471646c5153c9478c34e","_shrinkwrap":null,"_spec":"can-view-scope@3.1.0","_where":"/Users/kevin/dev/canjs","author":{"name":"Bitovi","email":"contact@bitovi.com","url":"http://bitovi.com"},"bit-docs":{"dependencies":{"bit-docs-glob-finder":"^0.0.5","bit-docs-dev":"^0.0.3","bit-docs-js":"^0.0.3","bit-docs-generate-readme":"^0.0.8"},"glob":{"pattern":"**/*.{js,md}","ignore":"node_modules/**/*"},"readme":{"apis":"./docs/apis.json"},"parent":"can-view-scope"},"browser":{"transform":["cssify"]},"browserify":{"transform":["cssify"]},"bugs":{"url":"https://github.com/canjs/can-view-scope/issues"},"dependencies":{"can-compute":"^3.0.0","can-construct":"^3.0.0","can-list":"^3.0.0","can-observation":"^3.0.1","can-simple-map":"^3.0.0","can-util":"^3.0.1"},"description":"Observable scopes","devDependencies":{"bit-docs":"0.0.7","can-define":"^1.0.1","can-map":"^3.0.0","cssify":"^0.6.0","done-serve":"^0.2.0","donejs-cli":"^0.8.0","generator-donejs":"^0.9.0","jshint":"^2.9.1","steal":"^0.16.0","steal-qunit":"^0.1.1","steal-tools":"^0.16.0","testee":"^0.2.4"},"directories":{},"dist":{"shasum":"1bcd00deba0c96531dfc471646c5153c9478c34e","tarball":"https://registry.npmjs.org/can-view-scope/-/can-view-scope-3.1.0.tgz"},"gitHead":"2a9c0fcc56d2404e90e121a7a86bc52a340a8c20","homepage":"http://canjs.com","keywords":["canjs","canjs-plugin","donejs"],"main":"can-view-scope","maintainers":[{"name":"daffl","email":"daff@neyeon.de"},{"name":"justinbmeyer","email":"justin@bitovi.com"},{"name":"matthewp","email":"matthew@matthewphillips.info"},{"name":"phillipskevin","email":"kphillips86@gmail.com"},{"name":"sinjhin","email":"john@ardea.io"}],"name":"can-view-scope","optionalDependencies":{},"readme":"ERROR: No README data found!","repository":{"type":"git","url":"git://github.com/canjs/can-view-scope.git"},"scripts":{"build":"node build.js","develop":"done-serve --static --develop --port 8080","document":"bit-docs","jshint":"jshint ./*.js --config","postversion":"git push --tags && git checkout master && git branch -D release && git push","preversion":"npm test && npm run build","release:major":"npm version major && npm publish","release:minor":"npm version minor && npm publish","release:patch":"npm version patch && npm publish","release:pre":"npm version prerelease && npm publish","test":"npm run jshint && npm run testee","testee":"testee test/test.html --browsers firefox","version":"git commit -am \"Update dist for release\" && git checkout -b release && git add -f dist/"},"system":{"configDependencies":["live-reload"],"npmAlgorithm":"flat"},"version":"3.1.0"},"signatures":[{"code":"new Scope(context, [parent], [meta] )","description":"\n","params":[{"types":[{"type":"*"}],"name":"context","description":"A value that represents the\ncurrent context. 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