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%define: accept unquoted values.

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* NEWS (2.5): Group all %define changes together, and document
this one.  Remove quotes in IELR and canonical LR entry.
* doc/bison.texinfo: Remove quotes in most examples throughout.
(Decl Summary): Update %define documentation.
(Table of Symbols): Likewise.
* src/ielr.c (LrType): Update documentation.
* src/parse-gram.y (content.opt): Add production for ID.
* tests/calc.at: Likewise.
* tests/existing.at: Likewise.
* tests/input.at: Likewise.
* tests/local.at: Likewise.
* tests/push.at: Likewise.
* tests/reduce.at: Likewise.
* tests/torture.at: Likewise.
(cherry picked from commit cf499cff31)

Conflicts:

	doc/bison.texinfo
	src/parse-gram.c
	src/parse-gram.h
	tests/actions.at
	tests/calc.at
This commit is contained in:
Joel E. Denny
2009-08-28 03:46:37 -04:00
parent 3a414bbfa0
commit f37495f601
13 changed files with 225 additions and 178 deletions
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72
doc/bison.texinfo
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@@ -4580,7 +4580,7 @@ The following Bison declaration says that you want the parser to be a push
parser (@pxref{Decl Summary,,%define api.push-pull}):
@example
%define api.push-pull "push"
%define api.push-pull push
@end example
In almost all cases, you want to ensure that your push parser is also
@@ -4591,7 +4591,7 @@ what you are doing, your declarations should look like this:
@example
%define api.pure
%define api.push-pull "push"
%define api.push-pull push
@end example
There is a major notable functional difference between the pure push parser
@@ -4640,14 +4640,14 @@ for use by the next invocation of the @code{yypush_parse} function.
Bison also supports both the push parser interface along with the pull parser
interface in the same generated parser. In order to get this functionality,
you should replace the @code{%define api.push-pull "push"} declaration with the
@code{%define api.push-pull "both"} declaration. Doing this will create all of
you should replace the @code{%define api.push-pull push} declaration with the
@code{%define api.push-pull both} declaration. Doing this will create all of
the symbols mentioned earlier along with the two extra symbols, @code{yyparse}
and @code{yypull_parse}. @code{yyparse} can be used exactly as it normally
would be used. However, the user should note that it is implemented in the
generated parser by calling @code{yypull_parse}.
This makes the @code{yyparse} function that is generated with the
@code{%define api.push-pull "both"} declaration slower than the normal
@code{%define api.push-pull both} declaration slower than the normal
@code{yyparse} function. If the user
calls the @code{yypull_parse} function it will parse the rest of the input
stream. It is possible to @code{yypush_parse} tokens to select a subgrammar
@@ -4664,8 +4664,8 @@ yypstate_delete (ps);
@end example
Adding the @code{%define api.pure} declaration does exactly the same thing to
the generated parser with @code{%define api.push-pull "both"} as it did for
@code{%define api.push-pull "push"}.
the generated parser with @code{%define api.push-pull both} as it did for
@code{%define api.push-pull push}.
@node Decl Summary
@subsection Bison Declaration Summary
@@ -4834,6 +4834,7 @@ already defined, so that the debugging facilities are compiled.
@end deffn
@deffn {Directive} %define @var{variable}
@deffnx {Directive} %define @var{variable} @var{value}
@deffnx {Directive} %define @var{variable} "@var{value}"
Define a variable to adjust Bison's behavior.
The possible choices for @var{variable}, as well as their meanings, depend on
@@ -4843,7 +4844,11 @@ Summary,,%language}, @pxref{Decl Summary,,%skeleton}).
It is an error if a @var{variable} is defined by @code{%define} multiple
times, but see @ref{Bison Options,,-D @var{name}[=@var{value}]}.
Omitting @code{"@var{value}"} is always equivalent to specifying it as
@var{value} must be placed in quotation marks if it contains any
character other than a letter, underscore, period, dash, or non-initial
digit.
Omitting @code{"@var{value}"} entirely is always equivalent to specifying
@code{""}.
Some @var{variable}s may be used as Booleans.
@@ -4851,12 +4856,12 @@ In this case, Bison will complain if the variable definition does not meet one
of the following four conditions:
@enumerate
@item @code{"@var{value}"} is @code{"true"}
@item @code{@var{value}} is @code{true}
@item @code{"@var{value}"} is omitted (or is @code{""}).
This is equivalent to @code{"true"}.
@item @code{@var{value}} is omitted (or @code{""} is specified).
This is equivalent to @code{true}.
@item @code{"@var{value}"} is @code{"false"}.
@item @code{@var{value}} is @code{false}.
@item @var{variable} is never defined.
In this case, Bison selects a default value, which may depend on the selected
@@ -4877,7 +4882,7 @@ Some of the accepted @var{variable}s are:
@item Accepted Values: Boolean
@item Default Value: @code{"false"}
@item Default Value: @code{false}
@end itemize
@item api.push-pull
@@ -4891,9 +4896,9 @@ Some of the accepted @var{variable}s are:
(The current push parsing interface is experimental and may evolve.
More user feedback will help to stabilize it.)
@item Accepted Values: @code{"pull"}, @code{"push"}, @code{"both"}
@item Accepted Values: @code{pull}, @code{push}, @code{both}
@item Default Value: @code{"pull"}
@item Default Value: @code{pull}
@end itemize
@item lr.default-reductions
@@ -4920,7 +4925,7 @@ More user feedback will help to stabilize it.)
@item Accepted Values:
@itemize
@item @code{"all"}.
@item @code{all}.
For @acronym{LALR} and @acronym{IELR} parsers (@pxref{Decl
Summary,,lr.type}) by default, all states are permitted to contain
default reductions.
@@ -4932,7 +4937,7 @@ That is, unlike in a canonical @acronym{LR} state, the lookahead sets of
reductions in an @acronym{LALR} or @acronym{IELR} state can contain
tokens that are syntactically incorrect for some left contexts.
@item @code{"consistent"}.
@item @code{consistent}.
@cindex consistent states
A consistent state is a state that has only one possible action.
If that action is a reduction, then the parser does not need to request
@@ -4944,7 +4949,7 @@ states, then a canonical @acronym{LR} parser reports a syntax error as
soon as it @emph{needs} the syntactically unacceptable token from the
scanner.
@item @code{"accepting"}.
@item @code{accepting}.
@cindex accepting state
By default, the only default reduction permitted in a canonical
@acronym{LR} parser is the accept action in the accepting state, which
@@ -4956,8 +4961,8 @@ without performing any extra reductions.
@item Default Value:
@itemize
@item @code{"accepting"} if @code{lr.type} is @code{"canonical-lr"}.
@item @code{"all"} otherwise.
@item @code{accepting} if @code{lr.type} is @code{canonical-lr}.
@item @code{all} otherwise.
@end itemize
@end itemize
@@ -4978,7 +4983,7 @@ are useless in the generated parser.
@item Accepted Values: Boolean
@item Default Value: @code{"false"}
@item Default Value: @code{false}
@item Caveats:
@@ -5020,7 +5025,7 @@ More user feedback will help to stabilize it.)
@item Accepted Values:
@itemize
@item @code{"lalr"}.
@item @code{lalr}.
While Bison generates @acronym{LALR} parser tables by default for
historical reasons, @acronym{IELR} or canonical @acronym{LR} is almost
always preferable for deterministic parsers.
@@ -5049,7 +5054,7 @@ investigate such problems while ignoring the more subtle differences
from @acronym{IELR} and canonical @acronym{LR}.
@end itemize
@item @code{"ielr"}.
@item @code{ielr}.
@acronym{IELR} is a minimal @acronym{LR} algorithm.
That is, given any grammar (@acronym{LR} or non-@acronym{LR}),
@acronym{IELR} and canonical @acronym{LR} always accept exactly the same
@@ -5063,7 +5068,7 @@ grammars, the number of conflicts for @acronym{IELR} is often an order
of magnitude less as well.
This can significantly reduce the complexity of developing of a grammar.
@item @code{"canonical-lr"}.
@item @code{canonical-lr}.
@cindex delayed syntax errors
@cindex syntax errors delayed
The only advantage of canonical @acronym{LR} over @acronym{IELR} is
@@ -5079,7 +5084,7 @@ Even when canonical @acronym{LR} behavior is ultimately desired,
facilitate the development of a grammar.
@end itemize
@item Default Value: @code{"lalr"}
@item Default Value: @code{lalr}
@end itemize
@item namespace
@@ -5460,8 +5465,8 @@ exp: @dots{} @{ @dots{}; *randomness += 1; @dots{} @}
More user feedback will help to stabilize it.)
You call the function @code{yypush_parse} to parse a single token. This
function is available if either the @code{%define api.push-pull "push"} or
@code{%define api.push-pull "both"} declaration is used.
function is available if either the @code{%define api.push-pull push} or
@code{%define api.push-pull both} declaration is used.
@xref{Push Decl, ,A Push Parser}.
@deftypefun int yypush_parse (yypstate *yyps)
@@ -5478,7 +5483,7 @@ is required to finish parsing the grammar.
More user feedback will help to stabilize it.)
You call the function @code{yypull_parse} to parse the rest of the input
stream. This function is available if the @code{%define api.push-pull "both"}
stream. This function is available if the @code{%define api.push-pull both}
declaration is used.
@xref{Push Decl, ,A Push Parser}.
@@ -5494,8 +5499,8 @@ The value returned by @code{yypull_parse} is the same as for @code{yyparse}.
More user feedback will help to stabilize it.)
You call the function @code{yypstate_new} to create a new parser instance.
This function is available if either the @code{%define api.push-pull "push"} or
@code{%define api.push-pull "both"} declaration is used.
This function is available if either the @code{%define api.push-pull push} or
@code{%define api.push-pull both} declaration is used.
@xref{Push Decl, ,A Push Parser}.
@deftypefun yypstate *yypstate_new (void)
@@ -5513,8 +5518,8 @@ allocated.
More user feedback will help to stabilize it.)
You call the function @code{yypstate_delete} to delete a parser instance.
function is available if either the @code{%define api.push-pull "push"} or
@code{%define api.push-pull "both"} declaration is used.
function is available if either the @code{%define api.push-pull push} or
@code{%define api.push-pull both} declaration is used.
@xref{Push Decl, ,A Push Parser}.
@deftypefun void yypstate_delete (yypstate *yyps)
@@ -9022,7 +9027,7 @@ in a file; Bison itself defines a class representing a @dfn{location},
a range composed of a pair of positions (possibly spanning several
files). The location class is an inner class of the parser; the name
is @code{Location} by default, and may also be renamed using
@code{%define location_type "@var{class-name}}.
@code{%define location_type "@var{class-name}"}.
The location class treats the position as a completely opaque value.
By default, the class name is @code{Position}, but this can be changed
@@ -9965,6 +9970,7 @@ Precedence}.
@deffn {Directive} %define @var{define-variable}
@deffnx {Directive} %define @var{define-variable} @var{value}
@deffnx {Directive} %define @var{define-variable} "@var{value}"
Define a variable to adjust Bison's behavior.
@xref{Decl Summary,,%define}.
@end deffn