Is SYMBOL-MACROLET supported?

[pamoroso]

Does Medley Common Lisp support symbol-macrolet? The only relevant symbol I can find is internal in the LOOP package where the only references in sources/XCL-LOOP, here and here, don't define or implement it.

Here is a test session in an XCL Exec in Medley Online (19-Mar-2024 02:06:49). The code snippets are from the HyperSpec.

2/8> (apropos "SYMBOL-MACROLET")
LOOP::SYMBOL-MACROLET
SYMBOL-MACROLET
IL:|{DSK}<home>medley>il>demo>SYMBOL-MACROLET.DRIBBLE;1|
SYMBOL-MACROLET
2/9> (symbol-macrolet ((x 'foo)) 
   (list x (let ((x 'bar)) x)))
Undefined car of form
SYMBOL-MACROLET

2/10> 

2/10> (symbol-macrolet ((x '(foo x))) 
   (list x))
Undefined car of form
SYMBOL-MACROLET

2/11>

There's another symbol-macrolet reference (in XCL-USER?) with no definition. This is a fresh XCL-USER session where I haven't evaluated the symbol symbol-macrolet prior to the above snippets.

[tfeb]

It would be interesting to see what happens when PCL is loaded, if it's not there by default. One of the motivations for symbol-macrolet was supporting things like with-slots, for instance.

My memory is too dim (and I am ashamed to say I don't use Medley very often), but I would not be at all surprised if PCL didn't have some hack to make it work. Perhaps not, though: it might have done it by code-walking things.

[pamoroso]

As far as I know PCL is loaded by default in Medley. It certainly was in the image I ran the tests in.

symbol-macrolet is indeed missing from Medley. The code in sources/XCL-LOOP is just a stub @masinter added to make Sacla loop work.

By the way we may turn this discussion into an issue to record the missing feature.