Re: A curious bug...

[Elias Mårtenson]

I don't have an answer. I'm going to have to have a look. Hopefully I'll have some time tomorrow.

Den tis 30 maj 2023 20:49Emmanuel Charpentier <emm.charpentier@free.fr> skrev:

Le mardi 30 mai 2023 à 12:26 +0200, Dr. Jürgen Sauermann a écrit :

Hi Emmanuel,

I cant quite explain this fully, but if I copy-and-paste your string below
and print it in hex, then:

eedjsa@server68:~/apl-1.8/src$ echo 'Z ← L foo R' | od -t x1z
0000000 5a 20 e2 86 90 20 4c 20 66 6f 6f 20 52 0a        >Z ... L foo R.<
0000016

which suggests that the sequence e2 86 90 (which, by chance, is
the UTF8 encoding of U+2190 aka. ←) made it into the tokenizer
of GNU APL (which then correctly complains).

In other words, it very much looks to me as if some conversion from
UTF8 encoding to Unicode (aka. UCS) is missing on the way of your
header line from emacs to APL.

Indeed. The $65536 question is therefore : "Why this substitution does not  miss when it reaches the interpreter distributed by GNU ?"  The gnu-apl machinery is the same...

Unfortunately I know very little as to how emacs works, maybe
Elias knows better how to troubleshoot this.

I'm as curious as you are... Since you Cc'd Elias, I just have to die of curiosity expecting his answer ;-)...

Again, thank you for your patience and attention !

--

Emmanuel Charpentier

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