Tweaked spelling and grammar.

[bison.git] / doc / bison.texinfo

diff --git a/doc/bison.texinfo b/doc/bison.texinfo
index b179e71de0c5090e796afc0ebb88856aa8255e8b..4ae798d5ac761120de3d15b09c9a2d9a57db75ea 100644 (file)
--- a/doc/bison.texinfo
+++ b/doc/bison.texinfo
@@ -93,8 +93,8 @@ Foundation
 Published by the Free Software Foundation @*
 59 Temple Place, Suite 330 @*
 Boston, MA  02111-1307  USA @*
 Published by the Free Software Foundation @*
 59 Temple Place, Suite 330 @*
 Boston, MA  02111-1307  USA @*

-Printed copies are available for $15 each.@*
-ISBN 1-882114-45-0
+Printed copies are available from the Free Software Foundation.@*
+ISBN 1-882114-44-2

 
 Permission is granted to make and distribute verbatim copies of
 this manual provided the copyright notice and this permission notice
 
 Permission is granted to make and distribute verbatim copies of
 this manual provided the copyright notice and this permission notice


@@ -323,12 +323,12 @@ This edition corresponds to version @value{VERSION} of Bison.
 @unnumbered Conditions for Using Bison
 
 As of Bison version 1.24, we have changed the distribution terms for
 @unnumbered Conditions for Using Bison
 
 As of Bison version 1.24, we have changed the distribution terms for

-@code{yyparse} to permit using Bison's output in non-free programs.
+@code{yyparse} to permit using Bison's output in nonfree programs.

 Formerly, Bison parsers could be used only in programs that were free
 software.
 
 The other GNU programming tools, such as the GNU C compiler, have never
 Formerly, Bison parsers could be used only in programs that were free
 software.
 
 The other GNU programming tools, such as the GNU C compiler, have never

-had such a requirement.  They could always be used for non-free
+had such a requirement.  They could always be used for nonfree

 software.  The reason Bison was different was not due to a special
 policy decision; it resulted from applying the usual General Public
 License to all of the Bison source code.
 software.  The reason Bison was different was not due to a special
 policy decision; it resulted from applying the usual General Public
 License to all of the Bison source code.


@@ -1499,7 +1499,7 @@ and continue parsing if the grammar contains a suitable error rule
 (@pxref{Error Recovery}).  Otherwise, @code{yyparse} returns nonzero.  We
 have not written any error rules in this example, so any invalid input will
 cause the calculator program to exit.  This is not clean behavior for a
 (@pxref{Error Recovery}).  Otherwise, @code{yyparse} returns nonzero.  We
 have not written any error rules in this example, so any invalid input will
 cause the calculator program to exit.  This is not clean behavior for a

-real calculator, but it is adequate in the first example.
+real calculator, but it is adequate for the first example.

 
 @node Rpcalc Gen, Rpcalc Compile, Rpcalc Error, RPN Calc
 @subsection Running Bison to Make the Parser
 
 @node Rpcalc Gen, Rpcalc Compile, Rpcalc Error, RPN Calc
 @subsection Running Bison to Make the Parser


@@ -1715,7 +1715,7 @@ as @code{sin}, @code{cos}, etc.
 
 It is easy to add new operators to the infix calculator as long as they are
 only single-character literals.  The lexical analyzer @code{yylex} passes
 
 It is easy to add new operators to the infix calculator as long as they are
 only single-character literals.  The lexical analyzer @code{yylex} passes

-back all non-number characters as tokens, so new grammar rules suffice for
+back all nonnumber characters as tokens, so new grammar rules suffice for

 adding a new operator.  But we want something more flexible: built-in
 functions whose syntax has this form:
 
 adding a new operator.  But we want something more flexible: built-in
 functions whose syntax has this form:
 


@@ -2254,7 +2254,7 @@ for @code{yylex}}).
 @item
 @cindex string token
 @cindex literal string token
 @item
 @cindex string token
 @cindex literal string token

-@cindex multi-character literal
+@cindex multicharacter literal

 A @dfn{literal string token} is written like a C string constant; for
 example, @code{"<="} is a literal string token.  A literal string token
 doesn't need to be declared unless you need to specify its semantic
 A @dfn{literal string token} is written like a C string constant; for
 example, @code{"<="} is a literal string token.  A literal string token
 doesn't need to be declared unless you need to specify its semantic


@@ -2272,7 +2272,7 @@ retrieve the token number for the literal string token from the
 By convention, a literal string token is used only to represent a token
 that consists of that particular string.  Thus, you should use the token
 type @code{"<="} to represent the string @samp{<=} as a token.  Bison
 By convention, a literal string token is used only to represent a token
 that consists of that particular string.  Thus, you should use the token
 type @code{"<="} to represent the string @samp{<=} as a token.  Bison

-does not enforces this convention, but if you depart from it, people who
+does not enforce this convention, but if you depart from it, people who

 read your program will be confused.
 
 All the escape sequences used in string literals in C can be used in
 read your program will be confused.
 
 All the escape sequences used in string literals in C can be used in


@@ -2321,7 +2321,7 @@ A Bison grammar rule has the following general form:
 @end example
 
 @noindent
 @end example
 
 @noindent

-where @var{result} is the nonterminal symbol that this rule describes
+where @var{result} is the nonterminal symbol that this rule describes,

 and @var{components} are various terminal and nonterminal symbols that
 are put together by this rule (@pxref{Symbols}).  
 
 and @var{components} are various terminal and nonterminal symbols that
 are put together by this rule (@pxref{Symbols}).  
 


@@ -2407,8 +2407,8 @@ with no components.
 A rule is called @dfn{recursive} when its @var{result} nonterminal appears
 also on its right hand side.  Nearly all Bison grammars need to use
 recursion, because that is the only way to define a sequence of any number
 A rule is called @dfn{recursive} when its @var{result} nonterminal appears
 also on its right hand side.  Nearly all Bison grammars need to use
 recursion, because that is the only way to define a sequence of any number

-of somethings.  Consider this recursive definition of a comma-separated
-sequence of one or more expressions:
+of a particular thing.  Consider this recursive definition of a
+comma-separated sequence of one or more expressions:

 
 @example
 @group
 
 @example
 @group


@@ -2868,7 +2868,7 @@ the parser, so that the function @code{yylex} (if it is in this file)
 can use the name @var{name} to stand for this token type's code.
 
 Alternatively, you can use @code{%left}, @code{%right}, or @code{%nonassoc}
 can use the name @var{name} to stand for this token type's code.
 
 Alternatively, you can use @code{%left}, @code{%right}, or @code{%nonassoc}

-instead of @code{%token}, if you wish to specify precedence.
+instead of @code{%token}, if you wish to specify associativity and precedence.

 @xref{Precedence Decl, ,Operator Precedence}.
 
 You can explicitly specify the numeric code for a token type by appending
 @xref{Precedence Decl, ,Operator Precedence}.
 
 You can explicitly specify the numeric code for a token type by appending


@@ -3189,7 +3189,7 @@ file in its own right.
 The output file @file{@var{name}.h} normally defines the tokens with
 Yacc-compatible token numbers.  If this option is specified, the
 internal Bison numbers are used instead.  (Yacc-compatible numbers start
 The output file @file{@var{name}.h} normally defines the tokens with
 Yacc-compatible token numbers.  If this option is specified, the
 internal Bison numbers are used instead.  (Yacc-compatible numbers start

-at 257 except for single character tokens; Bison assigns token numbers
+at 257 except for single-character tokens; Bison assigns token numbers

 sequentially for all tokens starting at 3.)
 
 @item %token_table
 sequentially for all tokens starting at 3.)
 
 @item %token_table


@@ -3218,7 +3218,7 @@ definitions for macros @code{YYNTOKENS}, @code{YYNNTS}, and
 @item YYNTOKENS
 The highest token number, plus one.
 @item YYNNTS
 @item YYNTOKENS
 The highest token number, plus one.
 @item YYNNTS

-The number of non-terminal symbols.
+The number of nonterminal symbols.

 @item YYNRULES
 The number of grammar rules,
 @item YYNSTATES
 @item YYNRULES
 The number of grammar rules,
 @item YYNSTATES


@@ -3384,9 +3384,9 @@ all others.  In this case, the use of the literal string tokens in
 the grammar file has no effect on @code{yylex}.
 
 @item
 the grammar file has no effect on @code{yylex}.
 
 @item

-@code{yylex} can find the multi-character token in the @code{yytname}
+@code{yylex} can find the multicharacter token in the @code{yytname}

 table.  The index of the token in the table is the token type's code.
 table.  The index of the token in the table is the token type's code.

-The name of a multi-character token is recorded in @code{yytname} with a
+The name of a multicharacter token is recorded in @code{yytname} with a

 double-quote, the token's characters, and another double-quote.  The
 token's characters are not escaped in any way; they appear verbatim in
 the contents of the string in the table.
 double-quote, the token's characters, and another double-quote.  The
 token's characters are not escaped in any way; they appear verbatim in
 the contents of the string in the table.


@@ -3591,7 +3591,7 @@ with no arguments, as usual.
 @cindex syntax error
 
 The Bison parser detects a @dfn{parse error} or @dfn{syntax error}
 @cindex syntax error
 
 The Bison parser detects a @dfn{parse error} or @dfn{syntax error}

-whenever it reads a token which cannot satisfy any syntax rule.  A
+whenever it reads a token which cannot satisfy any syntax rule.  An

 action in the grammar can also explicitly proclaim an error, using the
 macro @code{YYERROR} (@pxref{Action Features, ,Special Features for Use in Actions}).
 
 action in the grammar can also explicitly proclaim an error, using the
 macro @code{YYERROR} (@pxref{Action Features, ,Special Features for Use in Actions}).
 


@@ -4000,7 +4000,7 @@ expr:     expr '-' expr
 
 @noindent
 Suppose the parser has seen the tokens @samp{1}, @samp{-} and @samp{2};
 
 @noindent
 Suppose the parser has seen the tokens @samp{1}, @samp{-} and @samp{2};

-should it reduce them via the rule for the addition operator?  It depends
+should it reduce them via the rule for the subtraction operator?  It depends

 on the next token.  Of course, if the next token is @samp{)}, we must
 reduce; shifting is invalid because no single rule can reduce the token
 sequence @w{@samp{- 2 )}} or anything starting with that.  But if the next
 on the next token.  Of course, if the next token is @samp{)}, we must
 reduce; shifting is invalid because no single rule can reduce the token
 sequence @w{@samp{- 2 )}} or anything starting with that.  But if the next


@@ -4011,7 +4011,7 @@ results.
 To decide which one Bison should do, we must consider the
 results.  If the next operator token @var{op} is shifted, then it
 must be reduced first in order to permit another opportunity to
 To decide which one Bison should do, we must consider the
 results.  If the next operator token @var{op} is shifted, then it
 must be reduced first in order to permit another opportunity to

-reduce the sum.  The result is (in effect) @w{@samp{1 - (2
+reduce the difference.  The result is (in effect) @w{@samp{1 - (2

 @var{op} 3)}}.  On the other hand, if the subtraction is reduced
 before shifting @var{op}, the result is @w{@samp{(1 - 2) @var{op}
 3}}.  Clearly, then, the choice of shift or reduce should depend
 @var{op} 3)}}.  On the other hand, if the subtraction is reduced
 before shifting @var{op}, the result is @w{@samp{(1 - 2) @var{op}
 3}}.  Clearly, then, the choice of shift or reduce should depend


@@ -4617,7 +4617,7 @@ static int foo (lose);   /* @r{redeclare @code{foo} as function} */
 Unfortunately, the name being declared is separated from the declaration
 construct itself by a complicated syntactic structure---the ``declarator''.
 
 Unfortunately, the name being declared is separated from the declaration
 construct itself by a complicated syntactic structure---the ``declarator''.
 

-As a result, the part of Bison parser for C needs to be duplicated, with
+As a result, part of the Bison parser for C needs to be duplicated, with

 all the nonterminal names changed: once for parsing a declaration in which
 a typedef name can be redefined, and once for parsing a declaration in
 which that can't be done.  Here is a part of the duplication, with actions
 all the nonterminal names changed: once for parsing a declaration in which
 a typedef name can be redefined, and once for parsing a declaration in
 which that can't be done.  Here is a part of the duplication, with actions


@@ -4864,11 +4864,12 @@ with @samp{.tab.c}.  Thus, the @samp{bison foo.y} filename yields
 @menu
 * Bison Options::     All the options described in detail, 
                        in alphabetical order by short options.
 @menu
 * Bison Options::     All the options described in detail, 
                        in alphabetical order by short options.

+* Environment Variables::  Variables which affect Bison execution.

 * Option Cross Key::  Alphabetical list of long options.
 * VMS Invocation::    Bison command syntax on VMS.
 @end menu
 
 * Option Cross Key::  Alphabetical list of long options.
 * VMS Invocation::    Bison command syntax on VMS.
 @end menu
 

-@node Bison Options, Option Cross Key,  , Invocation
+@node Bison Options, Environment Variables,  , Invocation

 @section Bison Options
 
 Bison supports both traditional single-letter options and mnemonic long
 @section Bison Options
 
 Bison supports both traditional single-letter options and mnemonic long


@@ -4987,7 +4988,32 @@ bison -y $*
 @end example
 @end table
 
 @end example
 @end table
 

-@node Option Cross Key, VMS Invocation, Bison Options, Invocation
+@node Environment Variables, Option Cross Key, Bison Options, Invocation
+@section Environment Variables
+@cindex environment variables
+@cindex BISON_HAIRY
+@cindex BISON_SIMPLE
+
+Here is a list of environment variables which affect the way Bison
+runs.
+
+@table @samp
+@item BISON_SIMPLE
+@itemx BISON_HAIRY
+Much of the parser generated by Bison is copied verbatim from a file
+called @file{bison.simple}.  If Bison cannot find that file, or if you
+would like to direct Bison to use a different copy, setting the
+environment variable @code{BISON_SIMPLE} to the path of the file will
+cause Bison to use that copy instead.
+
+When the @samp{%semantic_parser} delcaration is used, Bison copies from
+a file called @file{bison.hairy} instead.  The location of this file can
+also be specified or overridden in a similar fashion, with the
+@code{BISON_HAIRY} environment variable.
+
+@end table
+
+@node Option Cross Key, VMS Invocation, Environment Variables, Invocation

 @section Option Cross Key
 
 Here is a list of options, alphabetized by long option, to help you find
 @section Option Cross Key
 
 Here is a list of options, alphabetized by long option, to help you find


@@ -5328,7 +5354,7 @@ A flag, set by actions in the grammar rules, which alters the way
 tokens are parsed.  @xref{Lexical Tie-ins}.
 
 @item Literal string token
 tokens are parsed.  @xref{Lexical Tie-ins}.
 
 @item Literal string token

-A token which constists of two or more fixed characters.
+A token which consists of two or more fixed characters.

 @xref{Symbols}.
 
 @item Look-ahead token
 @xref{Symbols}.
 
 @item Look-ahead token