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diff --git a/share/doc/psd/15.yacc/ss.. b/share/doc/psd/15.yacc/ss.. new file mode 100644 index 000000000000..7dd9ea84cdf9 --- /dev/null +++ b/share/doc/psd/15.yacc/ss.. @@ -0,0 +1,94 @@ +.\" Copyright (C) Caldera International Inc. 2001-2002. All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions are +.\" met: +.\" +.\" Redistributions of source code and documentation must retain the above +.\" copyright notice, this list of conditions and the following +.\" disclaimer. +.\" +.\" Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" All advertising materials mentioning features or use of this software +.\" must display the following acknowledgement: +.\" +.\" This product includes software developed or owned by Caldera +.\" International, Inc. Neither the name of Caldera International, Inc. +.\" nor the names of other contributors may be used to endorse or promote +.\" products derived from this software without specific prior written +.\" permission. +.\" +.\" USE OF THE SOFTWARE PROVIDED FOR UNDER THIS LICENSE BY CALDERA +.\" INTERNATIONAL, INC. AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR +.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED +.\" WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE +.\" DISCLAIMED. IN NO EVENT SHALL CALDERA INTERNATIONAL, INC. BE LIABLE +.\" FOR ANY DIRECT, INDIRECT INCIDENTAL, SPECIAL, EXEMPLARY, OR +.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF +.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR +.\" BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, +.\" WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE +.\" OR OTHERWISE) RISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN +.\" IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +.\" +.\" @(#)ss.. 8.1 (Berkeley) 6/8/93 +.\" +.\" $FreeBSD$ +.EH 'PSD:15-%''Yacc: Yet Another Compiler-Compiler' +.OH 'Yacc: Yet Another Compiler-Compiler''PSD:15-%' +.\".RP +.ND "July 31, 1978" +.TL +Yacc: +Yet Another Compiler-Compiler +.AU "MH 2C-559" 3968 +Stephen C. Johnson +AT&T Bell Laboratories +Murray Hill, New Jersey 07974 +.AI +.AB +.PP +Computer program input generally has some structure; +in fact, every computer program that does input can be thought of as defining +an ``input language'' which it accepts. +An input language may be as complex as a programming language, or as simple as +a sequence of numbers. +Unfortunately, usual input facilities +are limited, difficult to use, +and often are lax about checking their inputs for validity. +.PP +Yacc provides a general tool for describing +the input to a computer program. +The Yacc user specifies the structures +of his input, together with code to be invoked as +each such structure is recognized. +Yacc turns such a specification into a subroutine that +handles the input process; +frequently, it is convenient and appropriate to have most +of the flow of control in the user's application +handled by this subroutine. +.PP +The input subroutine produced by Yacc calls a user-supplied routine to +return the next basic input item. +Thus, the user can specify his input in terms of individual input characters, or +in terms of higher level constructs such as names and numbers. +The user-supplied routine may also handle idiomatic features such as +comment and continuation conventions, which typically defy easy grammatical specification. +.PP +Yacc is written in portable C. +The class of specifications accepted is a very general one: LALR(1) +grammars with disambiguating rules. +.PP +In addition to compilers for C, APL, Pascal, RATFOR, etc., Yacc +has also been used for less conventional languages, +including a phototypesetter language, several desk calculator languages, a document retrieval system, +and a Fortran debugging system. +.AE +.\" .OK +.\"Computer Languages +.\"Compilers +.\"Formal Language Theory +.\" .CS 23 11 34 0 0 8 |