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+FAQ (Frequently Asked Questions and answers) for SLIB Scheme Library (slib2a6).
+Written by Aubrey Jaffer (jaffer@ai.mit.edu).
+
+ INTRODUCTION AND GENERAL INFORMATION
+
+[] What is SLIB?
+
+SLIB is a portable scheme library meant to provide compatibiliy and
+utility functions for all standard scheme implementations.
+
+[] What is Scheme?
+
+Scheme is a programming language in the Lisp family.
+
+[] Which implementations has SLIB been ported to?
+
+SLIB is currently supported by Chez, ELK 2.1, GAMBIT, MacScheme,
+MITScheme, scheme->C, Scheme48, T3.1, SCM and VSCM
+
+[] How can I get SLIB?
+
+SLIB is available via ftp from:
+ ftp-swiss.ai.mit.edu:pub/scm/slib2a6.tar.gz
+ prep.ai.mit.edu:pub/gnu/jacal/slib2a6.tar.gz
+ ftp.maths.tcd.ie:pub/bosullvn/jacal/slib2a6.tar.gz
+ ftp.cs.indiana.edu:/pub/scheme-repository/imp/slib2a6.tar.gz
+
+SLIB is also included with SCM floppy disks.
+
+[] How do I install SLIB?
+
+Read the INSTALLATION INSTRUCTIONS in "slib/README".
+
+[] What are slib.texi and slib.info?
+
+"slib.texi" is the `texinfo' format documentation for SLIB.
+"slib.info" is produced from "slib.texi" by either Gnu Emacs or the
+program `makeinfo'. "slib.info" can be viewed using either Gnu Emacs
+or `info' or a text editor.
+
+Programs for printing and viewing TexInfo documentation (which SLIB
+has) come with GNU Emacs or can be obtained via ftp from:
+prep.ai.mit.edu:pub/gnu/texinfo-3.1.tar.gz
+
+[] How often is SLIB released?
+
+SLIB was released 9 times in 1993.
+
+[] What is the latest version?
+
+The version as of this writing is slib2a6.
+
+[] What version am I using?
+
+The Version is in the first line of the files slib/FAQ, slib/ANNOUNCE,
+and slib/README. If you have Scheme and SLIB running, type
+(slib:report-version)
+
+ SLIB INSTALLATION PROBLEMS
+
+[] When I load an SLIB initialization file for my Scheme
+ implementation, I get ERROR: Couldn't find "require.scm"
+
+Did you remember to set either the environment variable
+SCHEME_LIBRARY_PATH or the library-vicinity in your initialization
+file to the correct location? Make sure if you set only the
+environment variable SCHEME_LIBRARY_PATH that your implementation
+supports getenv.
+
+[] When I load an SLIB initialization file for my Scheme
+ implementation, I get ERROR: Couldn't find
+ "/usr/local/lib/slibrequire.scm"
+
+Notice that it is looking for "slibrequire.scm" rather than
+"slib/require.scm". You need to put a trailing slash on either the
+environment variable SCHEME_LIBRARY_PATH or in the library-vicinity in
+your initialization file.
+
+[] SLIB used to work, but now I get ERROR: Couldn't find
+ "slib/require.scm". What happened?
+
+You changed directories and now the relative pathname
+"slib/require.scm" no longer refers to the same directory. The
+environment variable SCHEME_LIBRARY_PATH and library-vicinity in your
+initialization file should be absolute pathnames.
+
+[] When I type (require 'macro) I get "ERROR: unbound variable:
+ require".
+
+You need to arrange to have your Scheme implementation load the
+appropriate SLIB initialization file ("foo.init") before using SLIB.
+If your implementation loads an initialization file on startup, you
+can have it load the SLIB initialization file automatically. For
+example (load "/usr/local/lib/slib/foo.init").
+
+[] Why do I get a string-ref (or other) error when I try to load
+ or use SLIB.
+
+Check that the version of the Scheme implementation you are using
+matches the version for which the SLIB initialization file was
+written. There are some notes in the SLIB initialization files about
+earlier versions. You may need to get a more recent version of your
+Scheme implementation.
+
+ USING SLIB PROCEDURES
+
+[] I installed SLIB. When I type (random 5) I get "ERROR:
+ unbound variable: random". Doesn't SLIB have a `random'
+ function?
+
+Before you can use most SLIB functions, the associated module needs to
+be loaded. You do this by typing the line that appears at the top of
+the page in slib.info (or slib.texi) where the function is documented.
+In the case of random, the line is (require 'random).
+
+[] Why doesn't SLIB just load all the functions so I don't have
+ to type require statements?
+
+SLIB currently has more than 1 Megabyte of Scheme source code. Many
+scheme implementations take unacceptably long to load 1 Megabyte of
+source; some implementations cannot allocate enough storage. If you
+use a package often, you can put the require statement in your Scheme
+initialization file. Consult the manual for your Scheme
+implementation to find out the initialization file's name.
+
+`Autoloads' will work with many Scheme implementations. You could put
+the following in your initialization file:
+ (define (random . args) (require 'random) (apply random args))
+
+I find that I only type require statements at top level when
+debugging. I put require statements in my Scheme files so that the
+appropriate modules are loaded automatically.
+
+[] Why does SLIB have PRINTF when it already has the more
+ powerful (CommonLisp) FORMAT?
+
+CommonLisp FORMAT does not support essential features which PRINTF
+does. For instance, how do you format a signed 0 extended number?
+
+ (format t "~8,'0,X~%" -3) ==> 000000-3
+
+But printf gets it right:
+
+ (printf "%08x\n" -3) ==> -0000003
+
+How can one trunctate a non-numeric field using FORMAT? This feature
+is essential for printing reports. The first 20 letters of a name is
+sufficient to identify it. But if that name doesn't get trucated to
+the desired length it can displace other fields off the page. Once
+again, printf gets it right:
+
+ (printf "%.20s\n" "the quick brown fox jumped over the lazy dog")
+ ==> the quick brown fox
+
+FORMAT also lacks directives for formatting date and time. printf
+does not handle these directly, but a related function strftime does.
+
+[] Why doesn't SLIB:ERROR call FORMAT?
+
+Format does not provide a method to truncate fields. When an error
+message contains non-terminating or large expressions, the essential
+information of the message may be lost in the ensuing deluge.
+
+FORMAT as currently written in SLIB is not reentrant. Until this is
+fixed exception handlers and errors which might occur while using
+FORMAT cannot use it.
+
+ MACROS
+
+[] Why are there so many macro implementations in SLIB?
+
+The R4RS committee specified only the high level pattern language in
+the Revised^4 Report on Scheme and left to the free marketplace of
+ideas the details of the low-level facility. Each macro package has a
+different low-level facility. The low-level facilities are sometimes
+needed because the high level pattern language is insufficiently
+powerful to accomplish tasks macros are often written to do.
+
+[] Why are there both R4RS macros and Common-Lisp style defmacros
+ in SLIB?
+
+Most current Scheme implementations predate the adoption of the R4RS
+macro specification. It turns out that all of the implementations
+can support defmacro natively.
+
+[] I did (LOAD "slib/yasos.scm"). The error I get is "variable
+ define-syntax is undefined".
+
+The way to load the struct macro package is (REQUIRE 'YASOS).
+
+[] I did (REQUIRE 'YASOS). Now when I type (DEFINE-PREDICATE
+ CELL?) The error I get is "variable define-predicate is
+ undefined".
+
+If like most implementations, your Scheme does not natively support
+R4RS macros you will need to install a macro-capable read-eval-print
+loop. This is done by:
+ (require 'macro) ;already done if you did (require 'yasos)
+ (require 'repl)
+ (repl:top-level macro:eval)
+
+This is also true for Schemes which don't support DEFMACRO. The lines
+in this case are:
+ (require 'repl)
+ (repl:top-level defmacro:eval)
+
+[] I always use R4RS macros. How can I avoid having to type
+ require statements every time I start Scheme?
+
+As is explained in the Repl entry in slib.info (or slib.texi):
+
+ To have your top level loop always use macros, add any interrupt
+ catching lines and the following lines to your Scheme init file:
+ (require 'macro)
+ (require 'repl)
+ (repl:top-level macro:eval)