Include use of TS declare syntax #583
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TS can use class fields with decorators without turning off useDefineForClassFields at the cost of losing inline initialisation see lit#479 and lit/lit#1985 for discussion
es2020 will cause useDefineForClassFields to default to true
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Requesting a review from @sorvell who wrote the current section. |
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@KeithHenry sorry this review took so long! The declare info was already added, but the es2020 bit wasn't, if you care to resubmit.
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| For **TypeScript**, you **may use class fields** for declaring reactive properties as long as the `useDefineForClassFields` setting in your `tsconfig` is set to `false`. Note, this is not required for some configurations of TypeScript, but it's recommended to explicitly set it to `false`. | |||
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| For **TypeScript**, you can use `declare` syntax for class fields that you explicitly want to exclude from the JS output regardless of the `useDefineForClassFields` setting. This will allow you to use decorators, but cannot be initialised inline. Similar to JS declared fields can only be initialised in the `constructor`. | |||
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Looks like this info was added at some point. It would be nice to get a link to https://www.typescriptlang.org/docs/handbook/2/classes.html#type-only-field-declarations in there though.
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TS can use class fields with decorators without turning off
useDefineForClassFieldsat the cost of losing inline initialisation.See #479 and lit/lit#1985 for discussion.
Also clarified version, as
es2020or above will causeuseDefineForClassFieldsto default totrue, not justesnext. See microsoft/TypeScript#45653