fix(runtime-core): trigger watcher with undefined as initial value #687
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posva
commented
Feb 3, 2020
| @@ -61,6 +61,9 @@ export type StopHandle = () => void | |||
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| const invoke = (fn: Function) => fn() | |||
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| // initial value for watchers to trigger on undefined initial values | |||
| const INITIAL_WATCHER_VALUE = {} | |||
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We could also use a Symbol but it shouldn't change anything since this variable is never exposed to user code
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hmm, since objects are unique your way is good too. But symbols can help e.g. in debug of Vue itself.
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But symbols can help e.g. in debug of Vue itself.
What case are you thinking of?
Symbols are also not supported by all platforms (even though we are using them in quite a few places already). To me, using an object works everywhere while being as simple as using Symbols and I couldn't think of a case where it would fail
cuongdevjs
approved these changes
Feb 4, 2020
yangmingshan
added a commit
to vue-mini/vue-mini
that referenced
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Mar 18, 2020
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Fix #683