Re: [csswg-drafts] [css-values] Actually describe how/whether computed math functions are simplified from specified ones (#2245)

The CSS Working Group just discussed `Actually describe how/whether computed math functions are simplified from specified ones`, and agreed to the following:

* `RESOLVED: Accept the proposed changes: We move where simplifiaction occurs from being consequence of serialization to happening on the underlying value`

<details><summary>The full IRC log of that discussion</summary>
&lt;dael> Topic: Actually describe how/whether computed math functions are simplified from specified ones<br>
&lt;dael> github: https://github.com/w3c/csswg-drafts/issues/2245<br>
&lt;dael> TabAtkins: Mostly a matter of if everyone else is cool with me doing spec work<br>
&lt;dael> TabAtkins: IN the spec calc and math functions are simplified during serialization. Has implicatiosn for typed OM b/c if not simplified I have to represent in a full version of what parsed<br>
&lt;AmeliaBR> +1 to Tab's proposal as described in the issue (any simplifications required for serialization should happen at parsing / setting time so they also show up in Typed OM)<br>
&lt;dael> TabAtkins: Didn't matter before b/c serialization was the only way to observe internal values. onw we have 2 ways want to make sure spec is clear simplification is on underlying value and then both emit simplified values, but don't simplify on their own<br>
&lt;dael> TabAtkins: Means we don't have to store another version of simplification for typed OM to emit<br>
&lt;dael> TabAtkins: Unless there's a reason to keep pre-simplification tree I'm going to say simplification is during parsing and serialization spits out the simplified thing<br>
&lt;dael> AmeliaBR: Agree with prop. There are consiquences for numeric precision. If you have calc with division and end result is not finitely represeted we agree post simplicafation is the cannonical presentation. That's how it works in brwosers so it's acknowledging how it works<br>
&lt;dael> dbaron: Confused in issue about which is parsing vs simplification<br>
&lt;dbaron> s/parsing vs simplification/computed vs specified values versus which is parsing vs serialization/<br>
&lt;dael> TabAtkins: b/c confused in spec. Simplification as spec now only happens as result of asking to serialize. THere's nothign sayings implification happens earlier. Typed OM doens't have a hook to get hte value serialization has and turn into object. Want to make sure emitting same thing. computed vs specified doesn't matter here<br>
&lt;dael> dbaron: No change to what spec values serialize to<br>
&lt;dael> TabAtkins: Correct. Assuming we say they serialize in a simplified manner then yes no change. Just moving where in proecss it happens. Unobservible to old code<br>
&lt;dael> dbaron: Worth checking that is the behavior. I didn't htin kit was<br>
&lt;kevers> present+, Kevin_Ellis<br>
&lt;dael> AmeliaBR: It is the current. If you set in an inline style font-size=calc10px/3 and you read back that style from a DOM, specified style, you get calc 3.3333px<br>
&lt;dael> dbaron: Then I'm fine<br>
&lt;dael> Rossen_: Hearing support. Any objections?<br>
&lt;dael> RESOLVED: Accept the proposed changes: We move where simplifiaction occurs from being consequence of serialization to happening on the underlying value<br>
&lt;dael> TabAtkins: Also, all of the text about computed values, serialization, all that in calc is outdated. Dates from values 3 with simple calc stuff. Now we have algebra none works.<br>
&lt;dael> TabAtkins: I'm filling in details and there's a link to those changes from the issue. Got a little more work to do on that, but I'll continue. Comments are appriciated. I'll fill in serialization. Goal is old calc is the same, need to handle the new stuff<br>
&lt;dael> TabAtkins: Anyone planning to work on this I'd love it if you review as you impl and if there's mistakes or improvements let me know<br>
</details>


-- 
GitHub Notification of comment by css-meeting-bot
Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/2245#issuecomment-537720775 using your GitHub account

Received on Wednesday, 2 October 2019 23:18:03 UTC