Operations names (add/sub/div/mul) like in WebAssembly

[munrocket]

Cmp() operator is used in sorting algorithms, but in math you usually want something like gte():

// current notation
if (a.cmp(b) == 1 || a.cmp(b) ==0) {
   // do something
};

// proposed notation
if (a.gte(b)) {
   // do something
}

Also names for basic operations add/sub/div/mul like in WebAssembly(Assembly) and in decimal.js is useful because it is much easier to write and read it. After some practice they feel like operator overloading +-/* and pretty readable.

let DEC = (x) => { new Decimal128(x) };
let costPrice = DEC('250'); // 250$
let profitPercent = DEC('30'); // 30%

//current notation
let sellPrice = profitPercent.add(DEC('100')).divide(DEC('100')).multiply(costPrice); //325$

//proposed notation
let sellPrice = profitPercent.add(DEC('100')).div(DEC('100')).mul(costPrice); //325$

End users can add DEC alias in context by hands if they need more compact expressions.

[munrocket]

@yaffle also suggested the same syntax simplification ideas and even proposed further: the D128 or Dec128 class to the global context.

[ljharb]

at the moment you'd do if (a.cmp(b) >= 0) {, which isn't that much worse than if (a.gte(b)) { (comparators don't have to return -1 or 1 for those cases, just any positive or negative number)

[munrocket]

Awesome, even better.

[jessealama]

In the latest version of the spec, the comparison operator cmp has been removed in favor of a lessThan and equals predicates. Does that address your concerns?

[jessealama]

I'm not wedded to the names of the operators. Aligning things with WebAssembly is not a bad idea.

[littledan]

I don't think the WebAssembly names were really chosen with the goal of being an interface for application developers. I prefer the more explicit names, but also it's fine to iterate on this until the proposal is proposed for Stage 2.7.

[jessealama]

Just to chime in with the status quo, as of today:

• We propose to use human-readable operation and comparison names ("multiply", "add", "lessThan", etc.) rather than the compact names used in WebAssembly and perhaps other languages.
• In earlier iterations of this proposal we used the name "cmp" but now use "compare".

[jessealama]

@Yaffle also suggested the same syntax simplification ideas and even proposed further: the D128 or Dec128 class to the global context.

Thanks! The moderately longer name "Decimal128", while admittedly bulky, does align with the goal of making things human-readable. It also suggests to the programmer that we're dealing with decimal numbers, and are aligning with IEEE 754 Decimal128, which is a named standard thing that a web search will turn up. Although most programmers (I assume!) have never heard of Decimal128, this strikes me as a reasonable name for a standard library object.