The new interfaces aren't required across the board, but would be used for the vast majority of situations. By specifying the "ASTLabelType=xxxxx;" and "TreeAdaptorType=yyyyy;" options, you could override the entire system.
This restructuring primarily affects the arguments and return values from various methods in the Tree and TreeAdaptor interfaces. Also, the new interfaces are MUCH simpler than they used to be. Methods which alter the tree are all moved to and unified in the TreeAdaptor, and many of the utility-type methods are moved to a new module instead of requiring every tree implementation to implement them. The previous interfaces were large, confusing (do you call tree.addChild or treeAdaptor.addChild?), and severely restricted my ability to create generic trees and a general purpose tree visualizer (similar to STViz but for parse results). Sam -----Original Message----- From: antlr-interest-boun...@antlr.org [mailto:antlr-interest-boun...@antlr.org] On Behalf Of Oliver Zeigermann Sent: Sunday, September 04, 2011 2:49 PM To: Terence Parr Cc: Antlr List Subject: Re: [antlr-interest] Using Tree Interface not plain Object What would be the benefit of introducing and then requiring those interfaces? Might make sense when you want to do automatic tree traversal, but maybe not when you want to create any kind of object where you might not even have a (single) parent or a flat list of children. Would it be possible to have both? Tree interfaces for homogeneous, normalized trees that can be processed further using ANTLR and whatever you want to generate if you do not want further ANTLR processing? - Oliver 2011/9/4 Terence Parr <pa...@cs.usfca.edu>: > Hi. Currently v3 requires nothing of your tree nodes; all you have to do is give me an adapter that says how to create them and navigate them and manipulate them. Users can set up ASTLabelType as an option so that $x in actions has the user's type instead of plain object. > > Sam Harwell and I were talking today about restructuring all of the tree interfaces. We're breaking it up into a hierarchy with Tree interface at the top. Tree just says you can get a payload, some children, and parent. ParseTree and AST split off as sub interfaces. We were thinking that it's pretty silly to use simple object when we could require the minimal Tree interface so at least code could display or navigate them. The reason I went with plain object originally was so people could use any existing object they have, even if they only have binary for it. This seems like a fairly extreme example and, in the worst case, somebody could wrap those objects so they were suitable for use with ANTLR. More than likely, somebody in that situation would simply use actions to construct the trees they want. Most trees not built for antlr expect everything in the constructor, whereas antlr has to build up the trees piecemeal as it parses. > > So, does anybody object to ANTLR assuming Tree in the parser if you are building trees and then AST in the tree parsers? > > Ter > > List: http://www.antlr.org/mailman/listinfo/antlr-interest > Unsubscribe: > http://www.antlr.org/mailman/options/antlr-interest/your-email-address > List: http://www.antlr.org/mailman/listinfo/antlr-interest Unsubscribe: http://www.antlr.org/mailman/options/antlr-interest/your-email-address List: http://www.antlr.org/mailman/listinfo/antlr-interest Unsubscribe: http://www.antlr.org/mailman/options/antlr-interest/your-email-address -- You received this message because you are subscribed to the Google Groups "il-antlr-interest" group. To post to this group, send email to il-antlr-inter...@googlegroups.com. To unsubscribe from this group, send email to il-antlr-interest+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/il-antlr-interest?hl=en.
