My apologies for the previous mail. There is a small correction, table 7.1 mentions that the next, & not first, un-suffixed element becomes the first child of the root. This seems in-consistent with the grammar rules mentioned in the earlier mail. Regards, Hitesh
On 8/10/10, Hitesh Shetty <[email protected]> wrote: > > Hello, > > First of all, Thank you Mr. Jim for your reply. > The question was actuall sent in reference to the Definite ANTLR reference, > table 7.1 found on page 176, which mentions that the first non-suffixed > element becomes the first child of the root of the subtree. This seemed > in-consistent with the grammar rules mentioned in the earlier mail. > > What is your opinion about this. > > Regards, > Hitesh > > On 8/9/10, Hitesh Shetty <[email protected]> wrote: >> >> Hi, >> >> Im a newbie ANTLR user and I had a basic question about the AST >> construction operator '^' caret, >> When the AST construction operator '^' (caret) is used along with a normal >> rule such as >> condStatement : 'expression' ^ x=statement1 (y=statement2)? ; >> The term 'expression' becomes the root for the tree and the next >> un-suffixed element i.e $x becomes the first child and $y becomes the second >> child. This can be rewritten as ^('expression' $x $y?). >> However when the operator '^' is used along with a subrule such as >> expr : x=INT ('+' ^ y=INT)* ; >> The $x is chosen as the first child not the next unsuffixed element i.e >> $y. For example input 1+2 is parsed as ^('+' 1 2) and not as ^('+' 2 1) >> Am I missing something obvious or Is this the behaviour of the AST >> construction operator ? >> Any pointers would be greatly appreciated. >> >> >> > > 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 [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/il-antlr-interest?hl=en.
