Why does this code fails to load?

[Boring Coder]

(define stringify

    []      -> "()"

    [skip]  -> ")"

    X       -> (str X) where (not (cons? X))

    [skip X | Y] -> (@s  (stringify X) " " (stringify [skip | Y]) )

    [X | Y] -> (@s "("  (stringify  X) " " (stringify [skip | Y]) ))

(defmacro quote

    [test X Y Z] -> [test X Y (stringify Z)])

(define test

    X Y Z -> [X Y Z])

This code fails to load

(0-) (load "simulator.shen")
fn: stringify is undefined

when I define stringify in the repl and then load

Heap exhausted during allocation: 119865344 bytes available, 260046856 requested.
        Immobile Object Counts
 Gen layout fdefn symbol   code  Boxed   Cons    Raw   Code  SmMix  Mixed  LgRaw LgCode  LgMix Waste%       Alloc        Trig   Dirty GCs Mem-age

[dr.mt...@gmail.com]

(defmacro quote

    [test X Y Z] -> [test X Y (stringify Z)])

goes into an infinite loop?

M.

[Boring Coder]

In my head it is  supposed to turn the third argument into a string before evaluating it. so    that :

(test (+2 2) (+3 3) (+ 5 5)) will give [4 6 "(+ 5 5)"]

but I think I didn't understand the order of macro-expansion and evaluation  correctly.

I will work on that.

[Bruno Deferrari]

It gives you [test 4 6 "(+ 5 5)"], which again matches the pattern [test X Y Z], which will be macro-expanded again, and again, and again.

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--

BD

[Bruno Deferrari]

My guess is that you wanted this instead?

(defmacro quote

    [test X Y Z] -> (test X Y (stringify Z)))

--

BD

[Boring Coder]

This is what I get with that when I enter everything in the repl :

(0-) (define stringify

    []      -> "()"

    [skip]  -> ")"

    X       -> (str X) where (not (cons? X))

    [skip X | Y] -> (@s  (stringify X) " " (stringify [skip | Y]) )

    [X | Y] -> (@s "("  (stringify  X) " " (stringify [skip | Y]) ))

(fn stringify)

(1-) (define test

    X Y Z -> [X Y Z])

(fn test)

(2-) (defmacro quote

    [test X Y Z] -> (test X Y (stringify Z)))

quote

(3-) (test (+ 3 3) (+ 2 2) (+ 5 5))

The value

  6

is not of type

  (OR FUNCTION SYMBOL)

when binding FUNCTION

And when I load the file it says this :

fn: test is undefined

[Bruno Deferrari]

Sorry, I misinterpreted what you were trying to do. You can use the original code you had, you just need to make a small change to the macro:

\\ Only expand if Z is not already a string

\\ avoids infinite recursive macro expansion

(defmacro quote
  [test X Y Z] -> [test X Y (stringify Z)]

     where (not (string? Z)))

or

\\ name the function differently, so that the quote macro

\\ doesn't match it again, avoiding infinite recursive expansion.

(define test-internal

  X Y Z -> [X Y Z])

(defmacro quote
  [test X Y Z] -> [test-internal X Y (stringify Z)]

--

BD