[racket] Define several procedures in a macro

Hi all,

I have yet another macro that uses eval!
And it is obvious from the previous discussion that it can be done without.

By the way, thanks for your answers, they were all very helpful!
(I think by mistake, I sent my thanks to Eli only and not to the whole 
mailing list).

The macro is used to define three procedures with provided name and 
fixed suffixes: "-simulation" "-mc" (for microcontroller) and "-vhdl".
It assembles three symbols that combine the provided name with the 
suffixes, then constructs procedure bodies in a list and finally uses 
eval-define combination to define the three procedures.
I suspect that instead of symbols I should construct identifiers and 
then they can be defined without eval, but have not been able to figure 
out a way to do that.

Here is the construction of the simulator procedure:

(define-syntax define-instruction
   (syntax-rules (sim)
     [(_ (name . args) (sim body-r ...))
      (begin
        (define name-string (symbol->string 'name))
        (define simulator-name
          (string->symbol
           (string-append
            name-string "-simulation")))
        (eval `(define (,simulator-name . args)
                 body-r ...)))]))

(define-instruction (hello a b c)
   (sim
    (+ a b c)))

(hello simulation 1 2 3)
;; > 6

Peter


;;; Some context for the interested
The macro is used in a larger system for writing custom processors with 
custom instructions (appication specific instruction processors (ASIPs)).
And the purpose for the macro is to define three procedures that 
represent processor instructions that can be used either to simulate 
instructions in a Racket REPL, to embed the instruction in a custom 
processor in VHDL, and to convert the actual sequence of instructions 
into machine code that can be executed on that processor in hardware.
The last two will be eventually combined

As an alternative, I am also working on an interpreter-like version that 
uses no macros.