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Comment by tgtweak | Hacker News Reader

Other than printing out the numbers, what are the practical applications?

Javascript was mentioned in the talk; because of its weak typing and plenty of APIs that take strings, floating point printing is pretty common.

That's really sad.

Why? Did you forget to read the implied "just like any other language that's being used in a graphical context, where live numbers need to be shown"?

Often, numbers in JS happen to be just integers. Would the implementation optimize for that case?

Javascript JITs specialize for integers already. I don't know if Ryū does specifically though.

It doesn't optimize for ints right now. I thought about that, but haven't tried it yet.

I mean, that's a huge practical application!

Real-time displays often need to show floating point numbers as they change. As a simple example, the time remaining display of a music player ticks down as the music plays. Now in this case, it is easy to fake it by using integers and then placing the decimal point, but if you were controlling something complex in real time you might not be able to do this as easily.

> it is easy to fake it by using integers and then placing the decimal point

That's not "faking it", that using fixed point numbers [1]. They are a great alternative if the numbers stay in roughly the same magnitude, and are much saner when dealing with e.g. money.

1: https://en.wikipedia.org/wiki/Fixed-point_arithmetic

Good point, and thanks. But if you are doing a real-time display (like an industrial controller, for example), you may not be able to choose a fixed point number as your source. I chose the music time example first because it is a common use of a number that needs to change in (almost) real time.

Printing them out quickly?

Cross platform serialization.

Web apis. Eg: json, xml

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