Error in Typescript Observable when using .startWith([])

I encountered the TypeScript error below:

Error:(34, 20) TS2345: Argument of type 'undefined[]' is not assignable to parameter of type 'number | Scheduler'. Type 'undefined[]' is not assignable to type 'Scheduler'. Property 'now' is missing in type 'undefined[]'.

when I tried using startWith in this particular context:

items$:any = Observable
        .interval(250)
        .map((_:any) => Math.random())
        .startWith([])
        .scan((acc:any, curr:any)=> [...acc, curr]);

Is there a way to cast the data to prevent this error?

Thanks,

Sean

typescriptangularrxjs

Answer №1

display = true;
elements$:any = Observable
    .interval(400)
    .delay(400)
    .map((_:any) => Math.random())
    .startWith(<any>[])
    .scan((accumulator:any, current:any)=> [...accumulator, current]);

including any made all the difference

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