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Lazy evaluation

See original GitHub issue

So if I use the and helper like so;

{{if (and firstExpression secondExpression)}}

It will evaluate both firstExpression and secondExpression even if firstExpression is false.

Is there a way to get it to evaluate just the firstExpression and stop there when it fails? The reason I ask is because 99% of the time my secondExpression is not necessary, and is quite taxing, so I only want to evaluate it when necessary.

I am trying to do this with ember-truth-helpers because both of my expressions are actually handlebar helpers :p

Issue Analytics

State:
Created 6 years ago
Comments:5

Top GitHub Comments

1reaction

rwjbluecommented, Oct 6, 2017

Sure, but definitely is annoying 😄

0reactions

Techn1xcommented, Oct 6, 2017

I guess in theory this would be an alternative approach to achieve lazy evaluation;

{{#if firstExpression}}
  {{#if secondExpression}}
    {{doSomething}}
  {{/if}}
{{/if}}

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