cannot set property in object with typescript

Question

export function collectAttributes(element: Element): AttributesInterface {
    return Array.from(element.attributes, ({ name, value }) => [
        name,
        value,
    ]).reduce((a, [key, val]) => {
        if (key.includes("@")) {
            let handlerName = key.replace("@", "")
            a.handlers.push([handlerName, val])
        } else if (key.startsWith("s:")) {
            let styleProp = key.replace("s:", "")
            a.bindedStyle.push([styleProp, val])
        } else if (key.startsWith("c:")) {
            let classProp = key.replace("c:", "");
            a.bindedClasses.push([classProp, val])
        } else if (key.startsWith("a:")) {
            let attributeProp = key.replace("a:", "");
            a.bindedAttr.push([attributeProp, val])
        } else if (key === "if") {
            a.show = val
        } else if (key.startsWith("p:")) {
            let prop = key.replace("p:", "");
            a.props[prop] = val  // <------ HERE
        } else {
            a.attr.push([key, val])
        }
        return a
    }, {
        attr: [],
        handlers: [],
        bindedStyle: [],
        bindedAttr: [],
        bindedClasses: [],
        show: null,
        visible: true,
        props: {},
        parent: element.parentElement,
        index: element.parentElement ? Array.prototype.indexOf.call(element.parentElement.children, element) : 0
    })
}
export interface AttributesInterface {
    attr: string[][],
    handlers: string[][],
    bindedStyle: string[][],
    bindedAttr: string[][]
    bindedClasses: string[][],
    show: string,
    visible: Boolean,
    parent: HTMLElement,
    index: number,
    props: { [key: string]: string }
}

I have the problem that i cannot set a new property. I have tried it to set { [key: string]: string } to my props object but it doesnt seems to fix the problem. I still get the error:

Element implicitly has an 'any' type because expression of type 'string' can't be used to index type '{}'. No index signature with a parameter of type 'string' was found on type '{}'.

Ifaruki Ifaruki · Accepted Answer · 2020-11-08T20:56:42

I have fixed it:

I have added the AttributesInterface to the accumulator of the reduce function

.reduce((a: AttributesInterface, [key, val]) => {

cannot set property in object with typescript

1 Answers