(Pub Feb.2013)

That book is old. Its called number now.

var SomeNumberAsAString = "1000";var a: number = <number><any>SomeNumberAsAString;

Also this assertion is very unsafe and I would not do this in production code. But it gets the point across :)

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A more up to date book chapter on assertions : https://basarat.gitbooks.io/typescript/content/docs/types/type-assertion.html

I've read @basarat's answer and decided to post my own since I strongly believe that there's still some room for explanation.

Be warned, <number><any> casting won't generate a number. In fact it will allow your code to be compiled (thus you'll pass all static typing checks) but it won't be a number in javascript. Consider this snippet of code:

let str = "1000";let a: number = <number><any>str;let b: number = parseInt(str); //or just let b = parseInt(str)console.log(typeof a); // stringconsole.log(typeof b); // number

I hardly can imagine cases when a-case is beneficial compared to b-case. I'd go with just parseInt or parseFloat or Number, whatever fits more. <T><any> casting looks smart but you must be 100% sure what you are supposed to achieve by that idiom.

And in most cases you probably don't want to achieve that )

Here is the cleanest way to do it.

const numberString = '1000';const a: int = numberString as any;