perf: always return void 0 as undefined node
#10243
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void 0 as undefined codevoid 0 as undefined node
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Maybe in the next major? |
nicolo-ribaudo
approved these changes
Jul 19, 2019
Sure. We would not get rid of it on 7.x |
jridgewell
approved these changes
Jul 23, 2019
This was referenced Sep 17, 2019
This was referenced Oct 3, 2019
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Effectively,
this.hasBinding("undefined")will always returns true sinceundefinedis a global property. Asvoid 0is safer thanundefined, here we remove theifconditional check.buildUndefinedNodewill be a bit faster as it doesn't have to look through the nested scopes.I would also suggest that we move
buildUndefinedNodeto babel-types and clearly state that it is not relevant to the Scope class.