[racket] Understanding raco make and its correctness guarantees

I am under the assumption that the compiled directory is just a cache
of the byte code version of the compiled source code, and that racket
should use the source code when ever that cache is invalid. This is
currently not true, as my examples show, yet racket does work to make
it mostly true. So my question is why doesn't racket do the same check
that raco make does?

No I don't want racket to run raco make before requiring the file.
That would update the compiled directories, (which likely isn't
expensive, but not the feature I'm asking about).

On Thu, Mar 21, 2013 at 8:34 AM, Tobias Hammer <tobias.hammer at dlr.de> wrote:
> You can use a little 'preload' script:
>
> wrap-compile.rkt
> #lang racket
> (require compiler/cm)
> (current-load/use-compiled
>  (make-compilation-manager-load/use-compiled-handler))
>
> and run with racket -t wrap-compile.rkt <more>
> I would really love to see this functionality as a command line option to
> the console racket
>
> Tobias
>
>
>
>
>
> On Thu, 21 Mar 2013 16:31:51 +0100, Eric Dobson <eric.n.dobson at gmail.com>
> wrote:
>
>> So anyone who just uses the command line tools is out of luck? I like
>> my build system to be correct, and it seems weird that there is work
>> to make sure the right zo file is matched with the source file but
>> that it is incorrect in some simple cases.
>>
>> On Thu, Mar 21, 2013 at 8:19 AM, Robby Findler
>> <robby at eecs.northwestern.edu> wrote:
>>>
>>> Or use DrRacket and turn on the auto compilation feature. Or set up
>>> compiler/cm yourself to do that.
>>>
>>> Robby
>>>
>>>
>>> On Thu, Mar 21, 2013 at 10:16 AM, Eric Dobson <eric.n.dobson at gmail.com>
>>> wrote:
>>>>
>>>>
>>>> That doesn't explain why I can get the same behavior as the macro with
>>>> a function call, probably inlining is responsible for that though.
>>>>
>>>> So the take away is that if I want my running system to represent the
>>>> current state of the source files I either need to run raco make every
>>>> single time, or never run raco make. That seems very counter
>>>> intuitive.
>>>>
>>>> On Thu, Mar 21, 2013 at 1:51 AM, Tobias Hammer <tobias.hammer at dlr.de>
>>>> wrote:
>>>> > The difference lies in the method how racket and raco make check for
>>>> > changes.
>>>> > - racket only looks at each individual file's timestamp source and .zo
>>>> > timestamp and uses whichever is never.
>>>> > - raco make always checks if the file has changed or any of its
>>>> > dependencies
>>>> > has changed to decide if it has to recompile the file.
>>>> >
>>>> > Whats happens in version 1 is that the macro is already expanded in
>>>> > a.zo
>>>> > and
>>>> > a.zo is still never than a.rkt. Therefore racket loads a.zo (but
>>>> > b.rkt)
>>>> > and
>>>> > prints 'version1.
>>>> > In version 2 raco make (or more correctly compiler/cm) checks a.rkt,
>>>> > finds
>>>> > the dependency to b.rkt, notices the change in b.rkt (by calculating a
>>>> > checksum over the whole dependency tree if i remember correct) and
>>>> > therefore
>>>> > recompiles a.rkt AND b.rkt.
>>>> >
>>>> > Version 3 should as far as i understand never differ, assumed raco
>>>> > make
>>>> > works.
>>>> >
>>>> > Tobias
>>>> >
>>>> >
>>>> >
>>>> > On Thu, 21 Mar 2013 06:23:24 +0100, Eric Dobson
>>>> > <eric.n.dobson at gmail.com>
>>>> > wrote:
>>>> >
>>>> >> I'm trying to understand what are the guarantees that raco make is
>>>> >> meant to provide. I'm going to limit this to simple programs, no
>>>> >> fancy
>>>> >> dynamic requires, or trying to trick the compiler.
>>>> >>
>>>> >> In the following scenario:
>>>> >> 1. Edit files
>>>> >> 2. run 'raco make <files>'
>>>> >> 3. Change files
>>>> >> I expect all of these to have the same effect during the running of
>>>> >> phase 0 when running racket.
>>>> >> 4. racket <main-file>
>>>> >> or
>>>> >> 4. raco make <files>
>>>> >> 5. racket <main-file>
>>>> >> or
>>>> >> 4. rm -rf compiled/
>>>> >> 5. raco make <files>
>>>> >> 6. racket <main-file>
>>>> >>
>>>> >> I can make version 1 and 2 differ with the following program:
>>>> >> a.rkt
>>>> >> #lang racket
>>>> >> (require "b.rkt")
>>>> >> (macro)
>>>> >>
>>>> >> #lang racket
>>>> >> (provide maco)
>>>> >> (define-syntax (macro stx)
>>>> >>   #''version1)
>>>> >>
>>>> >> Where the edit is changing version1 to version2. I can also replicate
>>>> >> this with a function and not a macro.
>>>> >>
>>>> >> I thought I could make version 2 and version 3 differ, but cannot
>>>> >> seem
>>>> >> to replicate it now, but it would be helpful to know if I see
>>>> >> something that is fixed by clearing the compiled directories.
>>>> >>
>>>> >> My understanding was that racket used the same logic as raco make on
>>>> >> whether or not to use the compiled versions versus recompiling, and
>>>> >> this seems to refute that. Can someone give some insight on what I
>>>> >> should be expecting?
>>>> >> ____________________
>>>> >>   Racket Users list:
>>>> >>   http://lists.racket-lang.org/users
>>>> >
>>>> >
>>>> >
>>>> > --
>>>> > ---------------------------------------------------------
>>>> > Tobias Hammer
>>>> > DLR / Robotics and Mechatronics Center (RMC)
>>>> > Muenchner Str. 20, D-82234 Wessling
>>>> > Tel.: 08153/28-1487
>>>> > Mail: tobias.hammer at dlr.de
>>>> ____________________
>>>>   Racket Users list:
>>>>   http://lists.racket-lang.org/users
>>>
>>>
>>>
>
>
> --
> ---------------------------------------------------------
> Tobias Hammer
> DLR / Robotics and Mechatronics Center (RMC)
> Muenchner Str. 20, D-82234 Wessling
> Tel.: 08153/28-1487
> Mail: tobias.hammer at dlr.de