Development Study/Frontend

[TypeScript] TypeScript Grammar - 09

TMInstaller 2023. 1. 8. 18:15
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[TypeScript] TypeScript Grammar - 08

Previous Series [TypeScript] TypeScript Grammar - 02 Previous Series [TypeScript] TypeScript Grammar - 01 1. Type Annotation TypeScript uses colon ( : ) behind variables to annotate a type const myMaxHamburger: number = 3; const answer: string = "Yes I can

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9.  Generic

If you use generic, you can recycle classes or interface to many types

When you declatate it, just write the parameters and decide types when it starts

function getSize<T>(arr: T[]): number {
	return arr.length;
}

const arr1 = [1, 2, 3];
getSize(arr1);// 3
getSize<number>(arr1);

const arr2 = ["a","b","c"];
getSize(arr2);// 3 
getSize<string>(arr2);// 3 

const arr3 = [false , true , true];
getSize(arr3);// 3 

const arr4 = [{}, {},{name:"Tim"}];
getSize(arr4);// 3

9_01.  Generic_interface 

interface Macbook<T> {
	name: string;
    price: number;
    option: T;
}

const m1 Macbook<object> = {
	name: "m1 air",
    price: 1500000,
    option: 
    {
    	color: "silvergray",
        coupon: false,
    },
}

const m2 Macbook<string> = {
	name: 'm2 air',
    price: 1800000,
    option: "not bad",
}

End

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