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TypeScript code kata list

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019 TypeScript - array.sort method

Duration

10 minutes

Brief

Creating a sorter for an array.

For more information

BING/GOOGLE: “TypeScript array sort”

Instructions

Get tutorial folder or the entire katas-typescript repo.
Open the [before/*.sln] file and execute the kata.
Feel free to execute this kata multiple times because repetition creates motor memory.

Github

• Before (start kata with this)
  
  • https://github.com/robertdunaway/katas-typescript/tree/master/019%20TypeScript%20-%20array.sort%20method/before
• After
  
  • https://github.com/robertdunaway/katas-typescript/tree/master/019%20TypeScript%20-%20array.sort%20method/after

Kata

Create a simple interface.

    interface pet {
        name: string;
        age: number;
        weight: number;
    }

Popular a new array based on the new interface.

    var myPets: pet[] = [
        { name: 'Sally', age: 18, weight: 85 },
        { name: 'Jasmine', age: 9, weight: 55 },
        { name: 'Rush', age: 15, weight: 45 },
        { name: 'Roxie', age: 6, weight: 85 }
    ];

Create a comparer based on age.

    var compareAge = function (a: pet, b: pet) {
        if (a.age > b.age) { return -1; }
        if (a.age < b.age) {return 1; }
        return 0;
    }

Output the sorted array to the console.

    console.log(myPets.sort(compareAge));

Create a comparer based on weight.

    var compareWeight = function (a: pet, b: pet) {
        if (a.weight > b.weight) { return -1; }
        if (a.weight < b.weight) { return 1; }
        return 0;
    }

Output the sorted array to the console.

    console.log(myPets.sort(compareWeight));

Next

Take a few minutes and imagine more examples.