@c -*-texinfo-*- @c This is part of the GNU Guile Reference Manual. @c Copyright (C) 1996, 1997, 2000, 2001, 2002, 2003, 2004 @c Free Software Foundation, Inc. @c See the file guile.texi for copying conditions. @iftex @page @unnumbered Preface This reference manual documents Guile, GNU's Ubiquitous Intelligent Language for Extensions. It describes how to use Guile in many useful and interesting ways. This is edition @value{MANUAL-EDITION} of the reference manual, and corresponds to Guile version @value{VERSION}. @end iftex @iftex @section Contributors to this Manual @end iftex @ifnottex @node Contributors @chapter Contributors to this Manual @end ifnottex The Guile reference and tutorial manuals were written and edited largely by Mark Galassi and Jim Blandy. In particular, Jim wrote the original tutorial on Guile's data representation and the C API for accessing Guile objects. Significant portions were contributed by Gary Houston (contributions to POSIX system calls and networking, expect, I/O internals and extensions, slib installation, error handling) and Tim Pierce (sections on script interpreter triggers, alists, function tracing). Tom Lord contributed a great deal of material with early Guile snapshots; although most of this text has been rewritten, all of it was important, and some of the structure remains. Aubrey Jaffer wrote the SCM Scheme implementation and manual upon which the Guile program and manual are based. Some portions of the SCM and SLIB manuals have been included here verbatim. Since Guile 1.4, Neil Jerram has been maintaining and improving the reference manual. Among other contributions, he wrote the Basic Ideas chapter, developed the tools for keeping the manual in sync with snarfed libguile docstrings, and reorganized the structure so as to accommodate docstrings for all Guile's primitives. Martin Grabmueller has made substantial contributions throughout the reference manual in preparation for the Guile 1.6 release, including filling out a lot of the documentation of Scheme data types, control mechanisms and procedures. In addition, he wrote the documentation for Guile's SRFI modules and modules associated with the Guile REPL. @iftex @section The Guile License @end iftex @ifnottex @node Guile License @chapter The Guile License @end ifnottex Guile is Free Software. Guile is copyrighted, not public domain, and there are restrictions on its distribution or redistribution, but these restrictions are designed to permit everything a cooperating person would want to do. @itemize @bullet @item The Guile library (libguile) and supporting files are published under the terms of the GNU Lesser General Public License version 2.1. See the file @file{COPYING.LIB}. @item The Guile readline module is published under the terms of the GNU General Public License version 2. See the file @file{COPYING}. @item The manual you're now reading is published under the terms of the GNU Free Documentation License (@pxref{GNU Free Documentation License}). @end itemize C code linking to the Guile library is subject to terms of that library. Basically such code may be published on any terms, provided users can re-link against a new or modified version of Guile. C code linking to the Guile readline module is subject to the terms of that module. Basically such code must be published on Free terms. Scheme level code written to be run by Guile (but not derived from Guile itself) is not resticted in any way, and may be published on any terms. We encourage authors to publish on Free terms. You must be aware there is no warranty whatsoever for Guile. This is described in full in the licenses. @iftex @section Layout of this Manual @end iftex @ifnottex @node Manual Layout @chapter Layout of this Manual @end ifnottex The manual is divided into five parts. @table @strong @item Part I: Introduction to Guile Provides an overview of what Guile is and how you can use it. A whirlwind tour shows how Guile can be used interactively and as a script interpreter, how to link Guile into your own applications, and how to write modules of interpreted and compiled code for use with Guile. Everything introduced here is documented again and in full by the later parts of the manual. This part also explains how to obtain and install new versions of Guile, and how to report bugs effectively. @item Part II: Writing and Running Guile Scheme @itemx Part III: Programming with Guile Document all aspects of practical programming using Guile. This covers both the Scheme level --- where we provide an introduction to the key ideas of the Scheme language --- and use of Guile's @code{scm} interface to write new primitives and objects in C, and to incorporate Guile into a C application. It also covers the use of Guile as a @acronym{POSIX}-compliant script interpreter and how to use the Guile debugger. @c @strong{Part V: Extending Applications Using Guile} explains the options @c available for using Guile as a application extension language. At the @c simpler end of the scale, an application might use Guile to define some @c application-specific primitives in C and then load an application Scheme @c file. In this case most of the application code is written on the @c Scheme level, and uses the application-specific primitives as an @c extension to standard Scheme. At the other end of the scale, an @c application might be predominantly written in C --- with its main @c control loop implemented in C --- but make occasional forays into Scheme @c to, say, read configuration data or run user-defined customization code. @c This part of the manual covers the complete range of application @c extension options. @item Part IV: Guile API Reference Documents Guile's core @acronym{API}. Most of the variables and procedures in Guile's core programming interface are available in both Scheme and C and are related systematically such that the C interface can be inferred from the Scheme interface and vice versa. Therefore, this part of the manual documents the Guile @acronym{API} in functionality-based groups with the Scheme and C interfaces presented side by side. Where the Scheme and C interfaces for a particular functional area do differ --- which is sometimes inevitable, given the differences in the structure of the two languages --- this is pointed out and explained. In all cases the overriding principle is that all the reference documentation for a given functional area is grouped together. @c the core Scheme language and features that Guile implements. Although @c the basis for this is the Scheme language described in R5RS, this part @c of the manual does not assume any prior familiarity with R5RS in @c particular, or with Scheme in general. Basic Scheme concepts, standard @c aspects of the Scheme language and Guile extensions on top of R5RS are @c all documented from scratch, and organized by functionality rather than @c by the defining standards. @item Part V: Guile Modules Describes some important modules, distributed as part of the Guile distribution, that extend the functionality provided by the Guile Scheme core. Two important examples are: @itemize @bullet @item The @acronym{POSIX} module, which provides Scheme-level procedures for system and network programming that conform to the @acronym{POSIX} standard. @item The @acronym{SLIB} module, which makes Aubrey Jaffer's portable Scheme library available for use in Guile. @end itemize @end table @iftex @section Manual Conventions @end iftex @ifnottex @node Manual Conventions @chapter Conventions used in this Manual @end ifnottex We use some conventions in this manual. @itemize @bullet @item For some procedures, notably type predicates, we use @dfn{iff} to mean ``if and only if''. The construct is usually something like: `Return @var{val} iff @var{condition}', where @var{val} is usually ``@nicode{#t}'' or ``non-@nicode{#f}''. This typically means that @var{val} is returned if @var{condition} holds, and that @samp{#f} is returned otherwise. To clarify: @var{val} will @strong{only} be returned when @var{condition} is true. @cindex iff @item In examples and procedure descriptions and all other places where the evaluation of Scheme expression is shown, we use some notation for denoting the output and evaluation results of expressions. The symbol @samp{@result{}} is used to tell which value is returned by an evaluation: @lisp (+ 1 2) @result{} 3 @end lisp Some procedures produce some output besides returning a value. This is denoted by the symbol @samp{@print{}}. @lisp (begin (display 1) (newline) 'hooray) @print{} 1 @result{} hooray @end lisp As you can see, this code prints @samp{1} (denoted by @samp{@print{}}), and returns @code{hooray} (denoted by @samp{@result{}}). Do not confuse the two. @c Add other conventions here. @end itemize @c Local Variables: @c TeX-master: "guile.texi" @c End: