Subject: =?Windows-1252?Q?RE:_[External]_:_bug#61281:_=93`(a_\, _b)=94_equals_to_?= “`(a . , b)”

From: Drew Adams <[email-masked]>
Date: Mon, 6 Feb 2023 05:22:00 +0000

> `(a  ,@ foo) ; ==> (a 4 5)
> `(a \,@foo)  ; ==> (a \,@ foo) - good
> `(a \,@ foo) ; ==> (a \,@ foo) - good
> 
> `(a  , foo) ; ==> (a 4 5)
> `(a \,foo)  ; ==> (a \,foo) - good
> `(a \, foo) ; ==> (a 4 5)   - bad, the bug case

Sorry for the typos in the comments.
This is what it is:

1. `(a  ,@ foo) ; ==> (a 4 5)
2. `(a \,@foo)  ; ==> (a \,@foo)  - good
3. `(a \,@ foo) ; ==> (a \,@ foo) - good

4. `(a  , foo) ; ==> (a (4 5))
5. `(a \,foo)  ; ==> (a \,foo) - good
6. `(a \, foo) ; ==> (a 4 5)   - bad, bug case

Note that #6 is not the same as #4.  It's not
just that the backslash made no difference.
#6 is the same as #1: the backslash made the
comma act like ,@.