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Re: alternative implementation of `??`

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En/Je/On 2015-10-19, Anton Ertl <anton@mips.complang.tuwien.ac.at>
escribió/skribis/wrote:

>>----
>>: ??  ( Compilation: "name" -- ) ( Runtime: f -- )
>>  postpone if  ' compile,  postpone then
>>  ; immediate
>>----

> This one does not deal with immediate words as intended.  E.g., in
> Gforth,
>
> ?? LEAVE
>
> would not work as intended.
>
> However, since you actually want to execute the compilation semantics,
> you can write the following in Gforth to express this:
>
>: ??  ( Compilation: "name" -- ) ( Runtime: f -- )
>   postpone if comp' execute postpone then ; immediate
>
> And the cool thing is that this works even for parsing words:
>
>: foo ?? ." bla bla" ;
> true foo  \ prints "bla bla"
> false foo \ prints nothing

Thank you for pointing out. This new version (for my system) works with
immediate and parsing words as you say:

----
: ??  ( Compilation: "name" -- ) ( Runtime: f -- )
  postpone if
  parse-name find-name  ( x 0 | cfa 1 | cfa -1 )
  dup 0= -13 ?throw
  1 = if  execute  else  compile,  then
  postpone then
  ; immediate
----

>>----
>>: ??  ( f -- )  0= if  r> cell+ >r  then  ;
>>----
>
> This requires a classical threaded-code implementation.

Yes, that's what it's for.

>>----
>>: (??)  ( f -- )  0= if  r> cell+ >r  then  ;
>>: ??  ( -- )  ?compiling postpone (??)  ; immediate
>>----

> Why spoil an ok word with STATE-smartness?  If you want it to be
> compile-only, implement a proper COMPILE-ONLY in the system (where the
> text-interpreter checks, not the word).

Of course. `compile-only` is on the to-do list... Meanwhile, some words
keep those checks.

-- 
Marcos Cruz
http://programandala.net

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alternative implementation of `??` Marcos Cruz <use_the_contact_page@programandala.net> - 2015-10-16 12:34 +0000
  Re: alternative implementation of `??` anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-10-19 09:29 +0000
    Re: alternative implementation of `??` Marcos Cruz <use_the_contact_page@programandala.net> - 2015-10-19 20:21 +0000

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