Implement a dead code elimination friendly strategy #4
Conversation
Instead of special casing `if` statements, feature flag call expressions
are now simply replaced by true or false literals when possible. This
lets you use feature flagging in more expressive ways by leaning on dead
code eliminiation in tools like Uglify. For example, now you can do
```js
if (isEnabled('foo') || isEnabled('bar')) {
// Uglify will be able to remove this code if both features are disabled
}
```
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http://marijnhaverbeke.nl/uglifyjs is useful if you want to experiment with the DCE |
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I'm concerned (slightly) that this is actually slightly different in the output for non-minified production builds of Ember. Specifically, today all disabled features are completely stripped but with this change they would not be stripped (both sides of the I'm certain that @mmun thought of this, but I wanted to make sure that we are all on the same page and that this is not something we are concerned with.... |
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@rwjblue I totally agree! We should tread carefully. Would be good to get Stef and Kris' thoughts as well. |
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💅 fancy |
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@rwjblue and I were pretty comfortable merging as is. If any complications occur we can always implement a dual strategy that handles |
Instead of special casing
ifstatements, feature flag call expressionsare now simply replaced by true or false literals when possible. This
lets you use feature flagging in more expressive ways by leaning on dead
code eliminiation in tools like Uglify. For example, now you can do
cc @mixonic @rwjblue @krisselden