[antlr-interest] Grammer question
Ney, Richard
richard.ney at aspect.com
Wed Nov 6 23:33:03 PST 2002
I have a question on formatting a grammer rule to construct the AST tree a
certain way. Say we have a grammer that allows these constructs
Construct 1) column1 + column2 alias1, column3
Construct 2) (column1 + column2) alias1, column3
Column1, column2 and alias as basic identifiers and the desired tree looks
like
alias1----
| |
| +----------
| |
| column1
| column2
column3
I figure I can do something with the ^ to make various item root. Also the
parens are option and I don't want them in the tree constuct. Is it possible
to combine ! and ?
-Richard
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