In With The New, Out With Old?

In With The New, Out With Old?

My first experience with TypeScript was with my Software Engineering class. While it was new for me (and new for the course), I found that it made JavaScript easier to read at least for myself. I am most used to statically typed languages. My past programming experiences are primarily in Java and C; my first attempt at this course being my only saving grace for the coursework. There is still much for me to refine in my own JavaScript/TypeScript knowledge, however, I do wholeheartedly look forward to expanding that knowledge.

While last semester was a particularly tempestuous period of time for me, I do recall learning JavaScript. I found that while it was leagues simpler than what I was used to, the dynamically typed nature of the language left me confused when skimming through longer code. Sometimes, debugging would take longer than necessary simply because I was so used to variable being defined with types. Errors being caught at the time of compiling allows for less chance with runtime errors as well, though I have not had a large enough project to fully experience this. Comparing two codes:

JavaScript

function feelsLike(temp, humidity) {
    const feels = -42.379 +
        (2.049 * temp) +
        (10.143 * humidity) -
        (0.2247 * temp * humidity) -
        (0.006837 * temp * temp) -
        (0.054817 * humidity * humidity) +
        (0.001228 * temp * temp * humidity) +
        (0.0008528 * temp * humidity * humidity) -
        (0.00000199 * temp * temp * humidity * humidity);
    
    const fL = "feels like ";

    if (feels <= 79) {
        return fL + feels + ": OK";
    } else if (feels >= 80 && feels <= 90) {
        return fL + feels + ": Caution";
    } else if (feels >= 91 && feels <= 102) {
        return fL + feels + ": Extreme Caution";
    } else if (feels >= 103 && feels <= 125) {
        return fL + feels + ": Danger";
    } else {
        return fL + feels + ": Extreme Danger";
    }
}

versus

Typescript

function feelsLike(temp: number, humidity: number) {
    const feels: number = -42.379 +
    (2.049 * temp) +
    (10.143 * humidity) -
    (0.2247 * temp * humidity) -
    (0.006837 * temp * temp) -
    (0.054817 * humidity * humidity) +
    (0.001228 * temp * temp * humidity) +
    (0.0008528 * temp * humidity * humidity) -
    (0.00000199 * temp * temp * humidity * humidity);
    
    const fL: string = "feels like ";

    if (feels <= 79) {
        return fL + feels + ": OK";
    } else if (feels >= 80 && feels <= 90) {
        return fL + feels + ": Caution";
    } else if (feels >= 91 && feels <= 102) {
        return fL + feels + ": Extreme Caution";
    } else if (feels >= 103 && feels <= 125) {
        return fL + feels + ": Danger";
    } else return fL + feels + ": Extreme Danger";
}

In essence, both code snippets are the same, however, in TypeScript it is much easier to pinpoint what is what. Of course, this is an incredibly rudimentary example, I look forward for the opportunity to work on larger projects using what I am currently learning. Where I used feelsLike(temp: number, humidity: number) in TypeScript is instead feelsLike(temp, humidity) in JS. It may be obvious, however, there is little clarification in the JavaScript snippet.

As the semester progresses, I hope to use both languages more. My understanding is still loose, especially in programming as a whole, so this offers me a an opportunity to lock in better my understanding while improving the bad habits I made over time.