TypeScript made me go back to web development again, bringing in the compile time type checks really makes it easier to write correct code faster.
But sometimes it is a little tricky to figure out the syntax. For example last night when I tried to store the result from an array.map call in a variable. Most of the examples I found used the var keyword and pretty much ignoring the type check making me wonder why even bother with TypeScript if you don't use the types?
So, I wanted to try the array.map in the render method of a React JSX file to render a list of items. The end result was something like this:
public render() { const itemNames: string[] = ["Item One", "Item Two"]; let itemNamesRender: JSX.Element[] = equipmentNames.map((name: string) => <li>{name}</li>); return <div> <h1>My Items</h1> <ul>{equipmentNamesRender}</ul> </div>; }
Where the
let result: JSX.Element[] = array.map()is the key. So pretty much just like all other variable declarations. The issue I had turned out to be that I didn't know that the type was JSX.Element, instead I was trying to force it to a string type.
Hope this helps someone out there. : )
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