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29 Jun
2020
29 Jun
'20
5:06 a.m.
Sorry, that was a bit too much oversimplification:
On 29 Jun 2020, at 12:36, Taco Hoekwater
wrote: In math mode, there *is* an expression state maintained, and that is why \over and \atop work.
Actually (still oversimplifying), the found commands are saved in a temporary list, that is then reprocessed once math mode has ended. And at that stage, an expression tree is built up. Best wishes, Taco