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A comment on It's 2023, so of course I'm learning Common Lisp. Parent comment

Re:It's 2023, so of course I'm learning Common Lisp by lispm on Thursday July 27, 2023 @03:05AM (#36889988)
> I have no clue what you're talking about

That's not good. Try again.

In Lisp adding two numbers looks like this is source code: (+ 1 2)

  CL-USER 41 > (+ 1 2)
  3
If I quote the expression and evaluate it, the result is (+ 1 2)

  CL-USER 42 > (quote (+ 1 2))
  (+ 1 2)
Thus in Lisp the textual representation of code and code as data are the same.

Not so in "Wolfram Language": a + b has a FullForm which looks differently. The user does not write ALL of the code in FullForm notation.

Source notation

  a + b
FullForm

  Plus[a, b]
Lisp:

Source notation

  (+ a b)
FullForm

  (+ a b)
Can you see the difference?

> Lol I am 100% sure that the majority of lisps cannot be aot compiled.

I'd expect that they can. That's a feature since 1962. SBCL for example does AOT compilation by default, always.

  * (disassemble (lambda (a) (+ a 42)))
  ; disassembly for (LAMBDA (A))
  ; Size: 36 bytes. Origin: #x7006DC83B4                        ; (LAMBDA (A))
  ; B4:       AA0A40F9         LDR R0, [THREAD, #16]            ; binding-stack-pointer
  ; B8:       4A0B00F9         STR R0, [CFP, #16]
  ; BC:       EA030CAA         MOV R0, R2
  ; C0:       8B0A80D2         MOVZ R1, #84
  ; C4:       3CAA80D2         MOVZ TMP, #1361
  ; C8:       BE6B7CF8         LDR LR, [NULL, TMP]              ; SB-KERNEL:TWO-ARG-+
  ; CC:       DE130091         ADD LR, LR, #4
  ; D0:       C0031FD6         BR LR
  ; D4:       E00120D4         BRK #15                          ; Invalid argument count trap
  NIL
Looks like native ARM64 code to me.
[ Parent | on HN ]
Re:It's 2023, so of course I'm learning Common Lisp by mathisfun123 on Thursday July 27, 2023 @03:18AM (#36890072)
> FullForm Plus[a, b]

How can I make this any more clear? You are able, in Mathematica, to write Plus[a, b] with your own fingers on your own keyboard and it will be interpreted as the same thing as a+b

> I'd expect that they can.

Clisp is not the only lisp - I can name 10 others that cannot be compiled.

[ Parent | on HN ]
Re:It's 2023, so of course I'm learning Common Lisp by kazinator on Thursday July 27, 2023 @03:39AM (#36890217)
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Re:It's 2023, so of course I'm learning Common Lisp by lispm on Thursday July 27, 2023 @03:58AM (#36890378)
Then the person should spend another weekend and implement a compiler for it.
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Re:It's 2023, so of course I'm learning Common Lisp by lispm on Thursday July 27, 2023 @03:56AM (#36890359)
> You are able, in Mathematica, to write Plus[a, b] with your own fingers on your own keyboard and it will be interpreted as the same thing as a+b

Sure, but it is not Mathematica's InputForm:

https://reference.wolfram.com/language/ref/InputForm.html

The majority of code is written not in FullForm. In Lisp 100% of the code is written in s-expressions.

> Clisp is not the only lisp - I can name 10 others that cannot be compiled.

Typical Lisp and Lisp dialects all can be compiled: Common Lisp, Emacs Lisp, ISLisp, Scheme, Racket, ...

Which Lisps can not be compiled?

[ Parent | on HN ]
Re:It's 2023, so of course I'm learning Common Lisp by mathisfun123 on Thursday July 27, 2023 @04:08AM (#36890435)
>Racket

Do you really know what you're talking about here?

https://docs.racket-lang.org/raco/make.html

>The raco make command accept filenames for Racket modules to be compiled to bytecode format.

That's not a compiler...

I don't claim to be an expert on lisp, so further googling I find

https://racket.discourse.group/t/chez-for-architectures-with...

which has some discussion about this and that native backend.

Suffice it to say I am not any more confident that being compilable is somehow intrinsic to lisp.

[ Parent | on HN ]
Re:It's 2023, so of course I'm learning Common Lisp by lispm on Thursday July 27, 2023 @05:00AM (#36890822)
From the Racket documentation:

https://docs.racket-lang.org/reference/compiler.html

"18.7.1.2 CS Compilation Modes

The CS implementation of Racket supports several compilation modes: machine code, machine-independent, interpreted, and JIT. Machine code is the primary mode, and the machine-independent mode is the same as for BC."

CS is the new implementation of Racket on top of the Chez Scheme runtime. Chez Scheme is known for its excellent machine code compiler.

"Machine code is the primary mode"

> Do you really know what you're talking about here?

Read above.

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Re:It's 2023, so of course I'm learning Common Lisp by kazinator on Thursday July 27, 2023 @01:41PM (#36897352)
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