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ember-let v0.7.1

A helper for binding values to HTMLBars template contexts


npm version Ember Observer Score Build Status

ember-let is an addon for binding variables to template contexts in Ember. It behaves much like the with helper, but lets you bind an arbitrary number of variables, including standalone values, hashes, and class instances. However, unlike with, the let helper will yield its block even if the bound values are undefined, null, or []. This has the benefit of allowing the user to treat the block values as true variable bindings rather than simply aliases to existing values.

See examples below:

Bind basic values

{{#let "abc" "123" as |first second|}}

Mix hashes and standalone values

{{#let (hash first="first" second="second") "third" as |hash standalone|}}

Bind a class instance returned from a helper

{{#let (boolean) as |bool|}}
  {{bool.value}} - <button onClick={{action bool.toggle}}>toggle</button>

Inline use Note: requires Ember 2.0+ (ie. does not support 1.13)

{{let greeting=(concat "hello " to)}}
{{greeting}} - <button {{action (action (mut to) "world")}}>Greet the world!</button>  

Inline let declarations are in scope until the parent element or block is closed, for example:

{{#if person.isActive}}
  {{!-- The name binding is not accessible here... --}}
{{!-- ...or here. -- }}


  • git clone this repository
  • npm install
  • bower install


  • ember server
  • Visit your app at http://localhost:4200.

Running Tests

  • npm test (Runs ember try:testall to test your addon against multiple Ember versions)
  • ember test
  • ember test --server


  • ember build

For more information on using ember-cli, visit

Code of Conduct

Please note that this project is released with a Contributor Code of Conduct. By participating in this project you agree to abide by its terms, which can be found in the file in this repository.


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