Re: [pure-lang-users] Proposed syntax changes

[Albert G. <Dr....@t-...>]

Albert Graef wrote:
> Albert Graef wrote:
>>> - search the directory of the script containing the using clause
>>>
>>> - failing that, search the cwd
>>>
>>> - failing that, search PURELIB
> 
> Ok, this is implemented now. I also threw in some script name 
> canonicalization and symbolic link resolution, details can be found in 
> the ChangeLog and in the DECLARATIONS section of the manpage.

I still wasn't satisfied with all this, so I gave it another thorough 
overhaul. The new search algorithm also puts to rest the non-portable 
workarounds which were necessary to load dynamic libraries in Pure 
scripts. I hope that this will do the job now. Here's the full blurb 
from the ChangeLog:

   The prelude is now *always* searched for in PURELIB only, to
   prevent code injection issues. Thus to use a custom prelude you'll
   have to set the PURELIB environment variable accordingly, or
   employ the '-n' option and explicitly specify the prelude on the
   command line.

   Scripts specified on the command line or with the 'run' command
   will *only* be searched for in the current directory.

   In addition to the PURELIB environment variable, new -I/-L command
   line options and PURE_INCLUDE/PURE_LIBRARY environment variables
   are now available to specify additional directories to search for
   source files and dynamic libraries specified using relative
   pathnames in 'using' clauses.

   For source scripts opened with a 'using' clause, the interpreter
   searches the following directories in the given order:

   - the directory of the script containing the 'using' clause (or
   the current working directory if the 'using' clause is read from
   standard input),

   - directories specified with -I, in the order in which they are
   specified on the command line,

   - directories specified in colon-separated format in the
   PURE_INCLUDE variable, in the order in which they are specified,

   - the PURELIB directory.

   Similarly, dynamic libraries are searched for in:

   - the directory of the script containing the 'using' clause (or
   the current working directory if the 'using' clause is read from
   standard input),

   - directories specified with -L, in the order in which they are
   specified on the command line,

   - directories specified in colon-separated format in the
   PURE_LIBRARY variable, in the order in which they are specified,

   - the PURELIB directory,

   - other platform-specific locations searched by the dynamic
   linker, such as system library directories and LD_LIBRARY_PATH on
   Linux.

   Note that in either case the current working directory is *not*
   searched by default (unless the 'using' clause is read from
   standard input), but of course you can force this by adding '.' to
   the corresponding search path.


-- 
Dr. Albert Gr"af
Dept. of Music-Informatics, University of Mainz, Germany
Email:  Dr....@t-..., ag...@mu...
WWW:    http://www.musikinformatik.uni-mainz.de/ag