REPL does not understand \Mu and \Nu

[eschnett]

The REPL does not complete the upper case greek letters \Mu and \Nu. The auto-generated tables call these letters \upMu and \upNu instead. This is counter-intuitive since all other upper case letters are available without an up prefix, e.g. \Alpha.

julia> versioninfo()
Julia Version 1.11.0-DEV.278
Commit 71570298a4 (2023-08-14 12:53 UTC)
Platform Info:
  OS: macOS (x86_64-apple-darwin22.6.0)
  CPU: 16 × Intel(R) Core(TM) i9-9980HK CPU @ 2.40GHz
  WORD_SIZE: 64
  LLVM: libLLVM-15.0.7 (ORCJIT, skylake)
  Threads: 1 on 16 virtual cores

[i9e1]

Input greek / sequence -> Output latin seems ok, but the other way around?
I'm unsure which latex packages defines \Alpha, as I'm used to the latin uppercase letters if they coincide with greeks.
Isn't the problem that that something like \Alpha works?

Lines 2677-2679 in #50913 :
Do you really want to reverse map latin M to greek \Mu?

[i9e1]

In unicode.xml your mentioned characters are defined as plain latin M, N, O as <latex> replacement. Its not a problem which is introduced by the REPL at all.
IMHO your approach (overwriting this downstream) is not the best to tackle this inconsistency.

unicode.xml
6966   │ <character id="U00391" dec="913" mode="math" type="alphabetic">
6967   │  <afii>2641</afii>
6968   │  <latex>\Alpha </latex>               <======= here explicit Latex escape sequence
...
6983   │  <description>GREEK CAPITAL LETTER ALPHA</description>
6984   │ </character>

...

7226   │ <character id="U0039C" dec="924" mode="math" type="alphabetic">
7227   │  <afii>264F</afii>
7228   │  <latex>M</latex>                         <==== here latin
...
7243   │  <description>GREEK CAPITAL LETTER MU</description>
7244   │ </character>

(I edited this a few times as researching unicode.xml was easier than I first thought)

[stevengj]

I tentatively agree that we should rationalize \upMu and \upNu to \Mu and \Nu, although these symbols have limited utility because of their resemblance to Latin symbols. These abbreviations happened in the initial automated import, which had some odd choices.

This should be an easy PR.

[stevengj]

Indeed, as far as I can tell the \up here stands for "upright" (ala the upgreek package) and not "uppercase". Which is silly for us to keep because our other Greek completions are upright by default.)