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Diffstat (limited to 'devel/bison20/pkg-descr')
| -rw-r--r-- | devel/bison20/pkg-descr | 22 |
1 files changed, 0 insertions, 22 deletions
diff --git a/devel/bison20/pkg-descr b/devel/bison20/pkg-descr deleted file mode 100644 index c968b052baf7..000000000000 --- a/devel/bison20/pkg-descr +++ /dev/null @@ -1,22 +0,0 @@ -Bison is a tool used to write parsers, such as the parser for GNU cc. -It is similar to Yacc, which is included in the base FreeBSD system. - -The main difference between Bison and Yacc that I know of is that -Bison supports the @N construction, which gives you access to -the starting and ending line number and character number associated -with any of the symbols in the current rule. - -Also, Bison supports the command `%expect N' which says not to mention -the conflicts if there are N shift/reduce conflicts and no reduce/reduce -conflicts. - -The differences in the algorithms stem mainly from the horrible -kludges that Johnson had to perpetrate to make Yacc fit in a PDP-11. - -Also, Bison uses a faster but less space-efficient encoding for the -parse tables (see Corbett's PhD thesis from Berkeley, "Static -Semantics in Compiler Error Recovery", June 1985, Report No. UCB/CSD -85/251), and more modern technique for generating the lookahead sets. -(See "Efficient Construction of LALR(1) Lookahead Sets" by F. DeRemer -and A. Pennello, in ACM TOPLS Vol 4 No 4, October 1982. Their -technique is the standard one now.) |