TeX - ! Extra alignment tab has been changed to \cr
doug at mathemaesthetics.com
Tue Jul 9 17:37:54 CEST 2019
I'd like to point out that Knuth's validation test for any TeX interpreter is a set of (as he has said, "diabolical") macros in a file called "trip.tex". It tests the situation under discussion, at line 408 in that file, causing the error message being complained of to be output to the "trip.log" file.
Assuming the error message is somehow faulty, that means that changing the wording of the error message will show up in any diff files between the older official reference log file and a new "trip.log" file, which in turn might mean failing TeX's complicated build process. That cost is likely too high to warrant changing the message's wording in any way, at least in the official TeX world that places a high value on compatibility with the past.
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