From: Christian Neukirchen <chneukirchen@...>
Date: 2006-04-27T06:09:01+09:00
Subject: Re: Rake task dependeny vs. method call

Joel VanderWerf <vjoel@path.berkeley.edu> writes:

> Trans wrote:
>> Just for fun I put together this simple demonstration.
>
> This _is_ kind of fun. Your demo suggests that maybe rake and dependency
> injection can be unified somehow.... For example, using my favorite DI toy:

Funnily, it's exactly the way I've implemented my experimental Rake
clone in Forth.  Enjoy:


#! /usr/bin/env gforth

\ Fake - Forth Make
\ A cheap clone of (proto-)Rake.
\
\ Copyright (C) 2006 Christian Neukirchen <chneukirchen@gmail.com>
\ Licensed under the same terms as Rake.  (MIT-style)

\ Missing:  - incremental task building
\           - file tasks
\
\ For file tasks, one would need to make the trigger big enough to
\ keep a file name and the mtime.  This is left as an exercise for the
\ reader.

\ A version of sh that is compilable.  (Rather useless without
\ variable interpolation.)
:noname
   sh ;
:noname
   35 parse  postpone sliteral
   postpone 2dup  postpone type  postpone cr    \ Display command
   postpone system ;                            \ Run command
interpret/compile: sh$

\ Late binding
: $  ( name -- )
   parse-word  postpone sliteral  postpone evaluate ; immediate

variable last-trigger           \ The address of the last defined trigger.

: new-trigger  ( -- )           \ Allocate, zero and store a new trigger.
   here cell allot  last-trigger !
   0 last-trigger @ ! ;

: trigger  ( -- a )             \ Compile the address of the current trigger.
   last-trigger @ postpone literal ; immediate

: trigger!  ( a -- )            \ Set the retrieved trigger.
   1 swap ! ;

: triggered?  ( a -- ? )        \ Task run?
   @ 0= ;

: task:  ( name -- )            \ Define a new task
   new-trigger
   :
   postpone trigger
   postpone triggered?
   postpone IF
   postpone trigger
   postpone trigger!
   ; immediate

: ;task  ( -- )                 \ End of task
   postpone THEN
   postpone ;
   ; immediate

: run-tasks  ( -- )
   argc @ 2 > IF
     argc @ 2 DO
       i arg  evaluate          \ Call all tasks.
     LOOP
   ELSE
     ." fake: No task given." cr
   THEN ;

: load-fakefile  ( -- )
   TRY
      s" Fakefile"  included
   RECOVER
      ." fake: No Fakefile found." cr
      bye
   ENDTRY ;

load-fakefile
run-tasks

bye


An example fakefile:

task: bla 
   $ quux
   ." hey, bla!" cr 
;task

task: quux
   $ bla
   ." hey, quux!" cr 
;task

task: a  $ b
   sh$ echo a
;task
task: b  $ a $ c $ d
   sh$ echo b
;task
task: c  $ b $ a
   sh$ echo c
;task
task: d  $ b
   sh$ echo d
;task


Example run:

#580<5|>lilith:~/mess/2006/09$ ./fake.f a
echo c
c
echo d
d
echo b
b
echo a
a

-- 
Christian Neukirchen  <chneukirchen@gmail.com>  http://chneukirchen.org