Error defining macro-defining macro

[TheGreatCatAdorer]

(let w (gensym W) x (gensym X) y (gensym Y) zs (gensym Zs)
  (defmacro declare-reduce-binary
    [declare [reduce-binary Name] | Declarations] ->
      (let macro-name (gensym Name)
        [[lambda x [lambda y y]]
         [defmacro macro-name
           [query reduce-binary Name] -> macro-name
           [Name w x y | zs] -> [Name w [Name x y | zs]]]
         [declare | Declarations]])))

error: The function SHEN::V154 is undefined. version:

Shen, copyright (C) 2010-2015 Mark Tarver
www.shenlanguage.org, Shen 22.2
running under Common Lisp, implementation: SBCL
port 3.0.3 ported by Mark Tarver, Robert Koeninger and Bruno Deferrari

[TheGreatCatAdorer]

Additionally, any further entries into the REPL error with The function SHEN::|declare-reduce-binary| is undefined.

[TheGreatCatAdorer]

Reads as

[LET* [[w [gensym [QUOTE W]]]
       [x [gensym [QUOTE X]]]
       [y [gensym [QUOTE Y]]]
       [zs [gensym [QUOTE Zs]]]]
  [defun [QUOTE declare-reduce-binary] [V20]
    [COND [[AND [CONSP [QUOTE V20]]
                [AND [EQ [CAR [QUOTE V20]] [QUOTE declare]]
                [AND [CONSP [CDR [QUOTE V20]]]
                [AND [CONSP [CAR [CDR [QUOTE V20]]]]
                [AND [EQ [CAR [CAR [CDR [QUOTE V20]]]] [QUOTE reduce-binary]]
                [AND [CONSP [CDR [CAR [CDR [QUOTE V20]]]]]
                     [NULL [CDR [CDR [CAR [CDR [QUOTE V20]]]]]]]]]]]]
             [LET [[macro-name [gensym [CAR [CDR [CAR [CDR [QUOTE V20]]]]]]]]
               [LIST [LIST [QUOTE lambda] x [LIST [QUOTE lambda] y y]]
                     [LIST [QUOTE defmacro] macro-name
                           [CONS [QUOTE query] [CAR [CDR [QUOTE V20]]]]
                           [QUOTE ->]
                           macro-name 
                           [CONS [CAR [CDR [CAR [CDR [QUOTE V20]]]]]
                                 [CONS w [CONS x [CONS y zs]]]]
                           [QUOTE ->]
                           [LIST [CAR [CDR [CAR [CDR [QUOTE V20]]]]]
                                 w
                                 [CONS [CAR [CDR [CAR [CDR [QUOTE V20]]]]]
                                       [CONS x [CONS y zs]]]]]
                     [CONS [QUOTE declare]
                           [CDR [CDR [QUOTE V20]]]]]]]
          [T [QUOTE V20]]]]]

[tizoc]

Hi @TheGreatCatAdorer. The defmacro declaration needs to be at the top level, you cannot put it inside a let (same applies to define). Another issue is that the expanded code cannot contain multiple forms, if you need that you have to wrap them in [package null [] ....] so that they become a single form.

Btw, for let bindings you should use upper-case names, otherwise the code may not be portable.