Version française
Home     About     Download     Resources     Contact us    

This site is updated infrequently. For up-to-date information, please visit the new OCaml website at

Browse thread
[Caml-list] a patch to support + and * in ocamlyacc
[ Home ] [ Index: by date | by threads ]
[ Search: ]

[ Message by date: previous | next ] [ Message in thread: previous | next ] [ Thread: previous | next ]
Date: 2003-10-17 (21:46)
From: Andrew Lenharth <andrewl@d...>
Subject: [Caml-list] a patch to support + and * in ocamlyacc
I find myself having to often implement rules such as:

foo_plus: foo {[$1]} | foo foo_plus {$1::$2} ;
foo_star: foo_plus {$1} | {[]} ;

in my parsers.  To get rid of this annoyance, here 
is a patch that add support for * and + to ocamlyacc.

it is a bit hackish, but even limited support for * and + makes
writting grammers less painful.

I modify get_name to check for + and *, and rewrite the name
it finds if those exist.  It also adds appropriate rules to a 
buffer to implement the rewritten name.  I change the read character
rutine such that at EOF I switch to the buffer holding the generated
rules.  This has been tested not to break the bootstrapping system.

An example:

%token <int> INT_LITERAL
%token EOF

%start main /* entry point */
%type <int list> main


Andrew Lenharth

To unsubscribe, mail Archives:
Bug reports: FAQ:
Beginner's list: