X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/6b98e4b5636203b60c2a43ddaa988562616b4c69..48c4080d0d214d22c30151b1161b0312bdc2c9fd:/NEWS?ds=sidebyside diff --git a/NEWS b/NEWS index 0dc40542..51836800 100644 --- a/NEWS +++ b/NEWS @@ -1,7 +1,20 @@ Bison News ---------- -Changes in version 1.49b: +Changes in version 1.49b, 2002-08-12: + +* GLR parsing + The declaration + %glr-parser + causes Bison to produce a Generalized LR (GLR) parser, capable of handling + almost any context-free grammar, ambiguous or not. The new declarations + %dprec and %merge on grammar rules allow parse-time resolution of + ambiguities. Contributed by Paul Hilfinger. + +* Output Directory + When not in Yacc compatibility mode, when the output file was not + specified, runnning `bison foo/bar.y' created `foo/bar.c'. It + now creates `bar.c'. * Undefined token The undefined token was systematically mapped to 2 which prevented @@ -17,6 +30,13 @@ Changes in version 1.49b: user specified that one of her tokens is numbered 256, then error will be mapped onto another number. +* Verbose error messages + They no longer report `..., expecting error or...' for state where + error recovery is possible. + +* End token + Defaults to `$end' instead of `$'. + * Error recovery now conforms to documentation and to POSIX When a Bison-generated parser encounters a syntax error, it now pops the stack until it finds a state that allows shifting the error @@ -29,9 +49,11 @@ Changes in version 1.49b: * Traces Popped tokens and nonterminals are now reported. -* Large grammars - Large grammars are now supported (large token numbers, large grammar - size (= sum of the LHS and RHS lengths), large LALR tables). +* Larger grammars + Larger grammars are now supported (larger token numbers, larger grammar + size (= sum of the LHS and RHS lengths), larger LALR tables). + Formerly, many of these numbers ran afoul of 16-bit limits; + now these limits are 32 bits on most hosts. * Explicit initial rule Bison used to play hacks with the initial rule, which the user does @@ -45,6 +67,10 @@ Changes in version 1.49b: * Useless rules, useless nonterminals They are now reported, as a warning, with their locations. +* Rules never reduced + Rules that can never be reduced because of conflicts are now + reported. + * Incorrect `Token not used' On a grammar such as @@ -67,7 +93,7 @@ Changes in version 1.49b: * Token end-of-file The token end of file may be specified by the user, in which case, the user symbol is used in the reports, the graphs, and the verbose - error messages instead of `$', which remains being the defaults. + error messages instead of `$end', which remains being the default. For instance %token YYEOF 0 or @@ -76,7 +102,8 @@ Changes in version 1.49b: * Semantic parser This old option, which has been broken for ages, is removed. -* New translation +* New translations + Brazilian Portuguese, thanks to Alexandre Folle de Menezes. Croatian, thanks to Denis Lackovic. * Incorrect token definitions @@ -108,6 +135,8 @@ Changes in version 1.49b: bar: '0' {} '0'; This is fixed. + +* GNU M4 is now required when using Bison. Changes in version 1.35, 2002-03-25: