update to stage 2.7 (#13)

tc39 · Apr 9, 2024 · f4286d0 · f4286d0
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diff --git a/README.md b/README.md
@@ -1,4 +1,4 @@
-# Math.sumExact
+# Math.sumPrecise
 
 A proposal to add a method to sum multiple values to JavaScript.
 
@@ -8,7 +8,7 @@ Authors: Kevin Gibbons
 
 Champions: Kevin Gibbons
 
-This proposal is at stage 2 of [the TC39 process](https://tc39.es/process-document/): the proposal has been accepted as a draft.
+This proposal is at stage 2.7 of [the TC39 process](https://tc39.es/process-document/): the proposal is approved in principle and now requires tests.
 
 ## Motivation
 
@@ -18,14 +18,14 @@ Also, summing a list of floating point numbers can be done more precisely than t
 
 ## Proposal
 
-Add an iterable-taking `Math.sumExact` method which returns the sum of the values in the iterable using a more precise algorithm than naive summation.
+Add an iterable-taking `Math.sumPrecise` method which returns the sum of the values in the iterable using a more precise algorithm than naive summation.
 
 ```js
 let values = [1e20, 0.1, -1e20];
 
 values.reduce((a, b) => a + b, 0); // 0
 
-Math.sumExact(values); // 0.1
+Math.sumPrecise(values); // 0.1
 ````
 
 ## Questions
@@ -46,29 +46,19 @@ So this proposal includes only an iterable-taking form.
 
 ### Naming
 
-`Math.sum` is the obvious name, but it's not obvious that this going to be a different (slower) algorithm than naive summation. This is tentatively called `Math.sumExact` to call attention to that difference.
-
-Since it differs from `Math.max` in taking an iterable, we might want a name which calls attention to that as well, such as `sumExactFrom`. See [issue #3](https://github.com/tc39/proposal-math-sum/issues/3) for discussion.
+`Math.sum` is the obvious name, but it's not obvious that this going to be a different (slower) algorithm than naive summation. This is called `Math.sumPrecise` to call attention to that difference.
 
 ### Should this coerce things to number, or throw if given something which is not a number?
 
-I want to [stop coercing things](https://github.com/tc39/how-we-work/pull/136), but `Math.max` is pretty strong precedent that we do coercion.
-
-As currently specified it will reject non-number values, breaking with precedent.
+It will reject non-number values, breaking with precedent from `Math.max`.
 
 ### Is the sum of an empty list 0 or -0?
 
-In some sense -0 is the right answer: that's the additive identity on floats.
-
-But in another sense the point is stick as close to real-number arithmetic as possible, and in the reals there is no -0.
-
-Python's `fsum` returns 0 when given an empty list.
-
-As currently specified this will return -0. This question remains open. See [issue #5](https://github.com/tc39/proposal-math-sum/issues/5) for discussion.
+It is -0. This is the floating point additive identity. This choice ensures that `Math.sumPrecise([]) + Math.sumPrecise(foo)` always gives the same answer as `Math.sumPrecise(foo)`.
 
 ### Should this work with BigInts?
 
-[No](https://github.com/tc39/proposal-bigint-math/issues/23) - it's important that `Math.sumExact()` returns the Number `-0` (or `0`), which means that `5n + Math.sumExact(bigints)` would throw when `bigints` is empty, which would be bad.
+[No](https://github.com/tc39/proposal-bigint-math/issues/23) - it's important that `Math.sumPrecise()` returns the Number `-0` (or `0`), which means that `5n + Math.sumPrecise(bigints)` would throw when `bigints` is empty, which would be bad.
 
 We could have seperate methods for summing BigInts. I'd vote for `BigInt.sum` or `BigInt.sumFrom`, depending on the outcome of the naming discussion above. But such a method will not be part of this proposal.
 

diff --git a/spec.html b/spec.html
@@ -1,9 +1,9 @@
 <!DOCTYPE html>
 <meta charset="utf-8">
 <pre class="metadata">
-title: Math.sumExact
+title: Math.sumPrecise
 status: proposal
-stage: 2
+stage: 2.7
 copyright: false
 contributors: Kevin Gibbons
 </pre>
@@ -18,8 +18,8 @@ <h1>Introduction</h1>
   <p>This proposal adds a method for summing multiple numbers.</p>
 </emu-clause>
 
-<emu-clause id="sec-math.sumexact">
-  <h1>Math.sumExact ( _items_ )</h1>
+<emu-clause id="sec-math.sumprecise">
+  <h1>Math.sumPrecise ( _items_ )</h1>
   <p>Given an iterable of Numbers, this function sums each value in the iterable and returns their sum. If any value is not a Number it throws a *TypeError* exception.</p>
   <p>It performs the following steps when called:</p>
   <emu-alg>