Re: [csswg-drafts] [cssom-view-1] Can scrollIntoView param type be more specifc?

Presumably the point is that for compat we want `scrollIntoView()` to act like be `scrollIntoView(true)` but `scrollIntoView(undefined)` to act like `scrollIntoView(false)`; that was certainly the reason for the initial non-use of an optional argument here and use of an overload instead, back when the first arg of the overload was not a dictionary.  If that's the case, it sure would be nice if someone just wrote this down, in a note, or comment, or something, so we don't have to keep coming back to it over and over again.

That said, I don't think Gecko's current IDL for this (presumably based on an earlier spec draft?)  has this property.  It looks like this:

    void scrollIntoView(boolean top);
    void scrollIntoView(optional ScrollIntoViewOptions options);

where `ScrollIntoViewOptions` has `ScrollLogicalPosition block = "start";`.  So passing either no arg or `undefined` will give the same behavior as passing `{ block: "center" }` or `true`.  The IDL in the spec now does have the property that passing nothing and passing undefined have different behavior.  @zcorpan When was it changed from the thing Gecko implements and why?  That might tell us what's going on here.

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Received on Friday, 2 June 2017 14:20:25 UTC