Avoid unintentional type conversions from Number to Array in Typescript

What is the best way to avoid implicit casting from a number to an array?

@Component
export default class FeedbackMain extends Vue {

currentState : Number = 0;

mounted () {
this.currentState = "Hello" //  Type '"Hello"' is not assignable to type 'Number'
this.currentState = data.filter(d => d.statetype === 0).map(d => d.state) // Not complaining
}

Answer №1

An error will be triggered, even if the array is of type any:

The type 'any[]' is missing the properties toFixed, toExponential, and toPrecision from type 'Number'

Can you confirm where your data variable is sourced? If data is of type any, then the result of the pipeline will also be of type any and can assign to any type.

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