[Dev-luatex] Re: Ignore null paragraph before display equation

On Sun, Feb 2, 2025 at 9:38 PM Udicoudco wrote:

On Sun, Feb 2, 2025 at 7:52 PM Hans Hagen wrote:

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On 2/2/2025 10:56 AM, Udicoudco wrote:

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Even though this change is less disruptive, there might be more concerns about backwards compatibility today than three years ago, if this is the case a new value to \matheqdirmode can be added.

I checked how I'd do it in luametatex and noticed a potential issue with the patch: because there can be more than one node (par plus plenty dir) you need to flush the list starting with vlink(head), otherwise you leak nodes.

(Because pop_nest is kind of dumb that should be enough but in other situations one should also set tail to head and the next node of head to null.)

(I actually added a bit more clever variant so that i can test some scenarios, but right now I can't forecast side effects as i have no clue about intended usage in macro packages as we don't need it in context.)

Oh, yes, a total oversight on my part... I intended to copy what is done in end_graf (which also suits the current behaviour that tests that vlink(head)==tail and flushes the tail, so flushing vlink(head) is the same).

wrong copy paste that worked for my too simplistic tests.

I'll test some more and send a new patch with the primitive and doc in a couple of hours.

I attached the patch with the new primitive, documentation, and the fix pointed by Hans (thanks for catching that early). Udi