Future/bison
1
0
Fork 0
mirror of https://git.savannah.gnu.org/git/bison.git synced 2026-03-09 12:23:04 +00:00
Code Issues Packages Projects Releases Wiki Activity

doc: document carets

Browse Source 
* NEWS: Announce it.
* doc/bison.texi (Bison Options):  Here.
This commit is contained in:
Theophile Ranquet
2012-12-04 13:12:12 +01:00
parent 505ece5171
commit 7bada5355e
2 changed files with 63 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

13
NEWS
View File

@@ -7,6 +7,19 @@ GNU Bison NEWS
The introduction of this feature, in 2.4, was four years ago. The --language The introduction of this feature, in 2.4, was four years ago. The --language
option and the %language directive are no longer experimental. option and the %language directive are no longer experimental.
** New format for error reports: carets
Caret errors have been added to Bison, for example (taken from the
documentation):
input.y:3.20-23: error: ambiguous reference: '$exp'
exp: exp '+' exp { $exp = $1 + $2; };
^^^^
The default behaviour for now is still not to display these unless explictly
asked with -fall of -fcaret. However, in a later release, it will be made the
default behavior (but may still be deactivated with -fno-caret).
** New value for %define variable: api.pure full ** New value for %define variable: api.pure full
The %define variable api.pure requests a pure (reentrant) parser. However, The %define variable api.pure requests a pure (reentrant) parser. However,

50
doc/bison.texi
View File

@@ -9239,6 +9239,56 @@ Treat warnings as errors.
A category can be turned off by prefixing its name with @samp{no-}. For A category can be turned off by prefixing its name with @samp{no-}. For
instance, @option{-Wno-yacc} will hide the warnings about instance, @option{-Wno-yacc} will hide the warnings about
POSIX Yacc incompatibilities. POSIX Yacc incompatibilities.
@item -f [@var{feature}]
@itemx --feature[=@var{feature}]
Activate miscellaneous @var{feature}. @var{feature} can be one of:
@table @code
@item caret
@itemx diagnostics-show-caret
Show caret errors, in a manner similar to GCC's
@option{-fdiagnostics-show-caret}, or Clang's @option{-fcaret-diagnotics}. The
location provided with the message is used to quote the corresponding line of
the source file, underlining the important part of it with carets (^). Here is
an example, using the following file @file{input.y}:
@example
%type <ival> exp
%%
exp: exp '+' exp @{ $exp = $1 + $2; @};
@end example
When invoked with @option{-fcaret}, Bison will report:
@example
@group
input.y:3.20-23: error: ambiguous reference: '$exp'
exp: exp '+' exp @{ $exp = $1 + $2; @};
^^^^
@end group
@group
input.y:3.1-3: refers to: $exp at $$
exp: exp '+' exp @{ $exp = $1 + $2; @};
^^^
@end group
@group
input.y:3.6-8: refers to: $exp at $1
exp: exp '+' exp @{ $exp = $1 + $2; @};
^^^
@end group
@group
input.y:3.14-16: refers to: $exp at $3
exp: exp '+' exp @{ $exp = $1 + $2; @};
^^^
@end group
@group
input.y:3.32-33: error: $2 of 'exp' has no declared type
exp: exp '+' exp @{ $exp = $1 + $2; @};
^^
@end group
@end example
@end table
@end table @end table
@noindent @noindent