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Subject: [wishlist] Attributes
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Hi all,

How many people out there are interested in seeing support for attribute
grammars? I know this topic has been raised before
it's just that automatically inheriting/synthesizing attributes such as
type and value throughout the tree saves a LOT of code.

Etienne doesn't want to have attributes on the SableCC generated nodes
and suggests storing them in a hashtable. I think you can still do this
with an attributed grammar. Just briefly: for the project I am working
on ATM I have written a simple grammar for defining attributes. This
grammar generates a tree walker that does all the work for you.

Here is an example snippet:
         name: String;
         type: String;
         size: Integer;

     /* attributes for a PVariableDeclaration: type, size */
     AVariableDeclaration: type[syn:TypeSpecifier], size[syn:TypeSpecifier];

The walker generated contains three hashtable (name, type, size) indexed
by SableCC nodes and provides getter methods. e.g.

     if (attributes.getType(node).equals("char")) { /* do something */ }

Thoughts? Comments?



Etienne M. Gagnon, Ph.D.                             egagnon@j-meg.com
President                                      http://www.sablevm.org/
J-Meg inc.                                     http://www.sablecc.org/