Re: ac-fs-separators.patch

[Akim Demaille]

Alexandre Oliva <address@hidden> writes:

> > So, how about starting from scratch here?  It's messy, and no one
> > knows exactly what kind of shell quotation must be used :(
> 
> What's your suggestion?

The confusion, IMHO, comes from the fact that sometimes you want to
expand some values (typically you want to run the value of
$ac_compile, not $ac_compile such it contains variables itself), and
other you don't (for instance when you write

AC_TRY_COMMAND([PATH=".;`pwd`"; conftest.sh])

you do not want to see `pwd` expanded in the log, and worse yet, you
don't want to see the `;' used to define PATH to be understood by eval
as a shell instruction separator.

So I suppose the right way to handle this is first enumerate the
situations we want to address, and see how they can be expressed in
terms of one another.  I guess AS_ESCAPE has a role to play.

Also, a serious problem I have (well, not a real one, just something
that bugs me), is that I'd like to avoid having to pass both the
command, and the logging command.  I can't find a mean to pass a
command to `eval', and given that command, log it.

This demonstrates my problem:

# _AC_EVAL(COMMAND)
# -----------------
# Eval COMMAND, save the exit status in ac_status, and log it.
AC_DEFUN([_AC_EVAL],
[_AC_RUN_LOG([eval $1],
             [eval echo "$as_me:__oline__: \"$1\""])])


# AC_RUN_LOG(COMMAND)
# -------------------
AC_DEFUN([AC_RUN_LOG],
[_AC_RUN_LOG([$1],
             [echo "$as_me:__oline__: AS_ESCAPE([$1])"])])


The two commands are completely different.


But maybe *I* am the problem because I am not consistent: when
AC_COMPILE I want to see the expanded value actually run, while here,
I want to see `pwd` although I should expect to see the actual value
of `pwd` in log.

I don't know.  I'm a bit lost, and can't concentrate :(