[antlr-interest] add new support methods in BaseTree?
Gerald Rosenberg
gerald at certiv.net
Wed Oct 22 14:10:51 PDT 2008
At 02:01 PM 10/22/2008, Terence Parr wrote:
>Hi, i'm thinking of adding this to BaseTree:
>
> /** Walk upwards looking for ancestor of this token type */
> public boolean hasAncestor(int ttype) {
> CommonTree t = this;
> t = t.parent;
> while ( t!=null ) {
> if ( t.getType()==ttype ) return true;
> t = t.parent;
> }
> return false;
> }
>
>and perhaps a few more context computations. In a tree grammar, you
>might want to do this:
>
>{((VecMathNode)input.LT(1)).hasAncestor(PRINT)}? ID // match only IDs
>in expr of print statements
>
>Any objections or votes in support?
Yes, this would be quite helpful. What other functions are you considering?
Gerald
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