Hy reader macros

[cory-patten2002]

Hi all,

I am trying to write a reader macro that converts valid hy into valid WGSL, I was using functions as extensions to the parser but I discovered the reader macro .dispatch and am trying to figure out how to use it correctly. I have had deep conversations with deepseek about this issue but most of its responses are nonsense. Attached is the code the lines to look out for are line 1 and line 75. Line 1 is where I define the reader and line 75 is where I attempt to call it. If anyone could give me some pointers that would be greatly appreciated.

Kind regards,
Cory Patten

[cory-patten2002]

It didn't attach because .hy is not recognised by github

(defreader binding
    (.slurp-space &reader)
    (assert (.peek-and-getc &reader "("))
    (setv name (.read_ident &reader))
    (.slurp-space &reader)
    (setv group None)
    (setv binding None)
    (setv buffer-type None)
    (setv access None)
    (setv data-type None)
    (while (not (.peek-and-getc &reader ")"))
        (setv ident (.read_ident &reader))
        (.slurp-space &reader)
        (match ident
            ":group" (setv group (.read_ident &reader))
            ":binding" (setv binding (.read_ident &reader))
            ":buffer-type" (setv buffer-type (.read_ident &reader))
            ":access-mode" (setv access (.read_ident &reader))
            ":type" (setv data-type (.read_ident &reader)))
        (.slurp-space &reader)) 
    f"@group({group}) @binding({binding}) var<{buffer-type}, {access}> {name}: {data-type};\n")
(defreader compute
    (.slurp-space &reader)
    (setv symbol(.read_ident &reader :just_peeking False))
    (.slurp-space &reader)
    (assert (.peek-and-getc &reader "["))
    (setv workgroup-x (.read_ident &reader :just_peeking False))
    (.slurp-space &reader)
    (setv workgroup-y (.read_ident &reader :just_peeking False))
    (.slurp-space &reader)
    (setv workgroup-z (.read_ident &reader :just_peeking False))
    (assert (.peek-and-getc &reader "]"))
    (.slurp-space &reader)
    (assert (.peek-and-getc &reader "["))
    (setv bindings "")
    (while (not (.peek-and-getc &reader "]"))
            (+= bindings (.dispatch &reader "#binding")) 
            (.slurp-space &reader))
    (.slurp-space &reader)
    (assert (.peek-and-getc &reader "["))
    (setv params (param &reader))
    (.slurp-space &reader)
    (while (not (.peek-and-getc &reader "]"))
        (+= params "," (param &reader))
        (.slurp-space &reader))
    (.slurp-space &reader)
    (setv body (expression &reader))
    f"{bindings}@compute @workgroup_size({workgroup-x}, {workgroup-y}, {workgroup-z})\nfn {symbol}({params}){{{body}}}")

[cory-patten2002]

OMFG your reader macros are so broken calling .reader_table &reader results in error

[cory-patten2002]

(defreader reader-table
    (setv table (.reader_table &reader))
    table)

This is the code I have to check the reader table and it returns; hy.reader.exceptions.LexException: 'dict' object is not callable

[Kodiologist]

I have had deep conversations with deepseek about this issue but most of its responses are nonsense.

I don't think there's enough training data for LLMs to be very helpful with Hy.

To be clear, the methods dispatch and reader_table are not themselves reader macros.

OMFG your reader macros are so broken calling .reader_table &reader results in error

It's not broken just because you didn't read the error message. Like it and the documentation says, reader_table is a dictionary, not a method, so you want to say &reader.reader_table or (. &reader reader_table) in place of (.reader_table &reader).

[cory-patten2002]

For more context line 91 is where the issue comes in

[cory-patten2002]

And how do I import reader macros into another file?

[cory-patten2002]

This test file

(require .macros :readers [compute])

(print (hy.repr #compute [1 1 1] [test :group 0 :binding 0 :buffer-type storage :access-mode read_write :type vec2f] [(test :type vec2f)] (+ 1 1)))

Returns the error

hy.errors.HyMacroExpansionError:
  File "C:\Users\neko\home\Documents\code\hy-render\test.hy", line 1
    (require .macros :readers [compute])
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
expanding macro require
  TypeError: the 'package' argument is required to perform a relative import for '.macros'

Please tell me what I am doing wrong cause it appears from previous errors this has been fixed. Let me know where I can make pull requests to fix this.

[Kodiologist]

Sounds like you're in the process of figuring things out. Try doing what you can and then asking a specific question rather than posting a series of stream-of-consciousness comments. (Also, I'd prefer you find minimal examples of a problem rather than ask me to debug 94-line code blocks.)

[Kodiologist]

Let me know where I can make pull requests

https://github.com/hylang/hy/pulls . See the contributor guidelines.