Michael Heerdegen <michael_heerdegen@web.de> writes:

> Sho Takemori <stakemorii@gmail.com> writes:
>
>> By expanding map-put, I found that it returns a new list if "m" is a
>> list and the key is not in "m".
>
> Indeed, good catch.
>
> The implementation of `map-put' is wrong: it binds the evaluated place
> expression to a new symbol and uses that symbol as place to operate on.
>
> The intention presumably was to avoid code duplication in the macro
> expansion - which is good - but it fails to change the original place.

Indeed, it is wrong.  I will have a look at the issue.

Nico