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First usable sidewalks theme

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This commit is contained in:
Pieter Vander Vennet 2021-10-22 18:53:07 +02:00
parent 02a1d9696f
commit ff0ee35ec1
19 changed files with 537 additions and 174 deletions
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14
Logic/UIEventSource.ts
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@ -109,6 +109,20 @@ export class UIEventSource<T> {
promise?.catch(err => src.setData({error: err}))
return src
}
public withEqualityStabilized(comparator: (t:T | undefined, t1:T | undefined) => boolean): UIEventSource<T>{
let oldValue = undefined;
return this.map(v => {
if(v == oldValue){
return oldValue
}
if(comparator(oldValue, v)){
return oldValue
}
oldValue = v;
return v;
})
}
/**
* Given a UIEVentSource with a list, returns a new UIEventSource which is only updated if the _contents_ of the list are different.