Chris Yocum wrote:
Hi Everyone, I am not sure if this is the correct list to post this problem to but I will try here first.
The main Parrot list is better for anything not specifically related to the Perl 6 compiler.
I am having a problem with understanding TGE and I was hoping someone might be able to give me some help. I am writing a parrot version of 1964 BASIC using the compiler tools and I have the PGE part nearly complete (there are a few things that I need to finish though) and I was looking forward to using TGE but I have become stuck. My problem is that when I get through the first two parts of the tree, I come to a point where things come to a screeching halt because the node (in Basic64::Grammar::statement) does not seem to be anything at all or anything that I can identify. I know from the parse output that Basic64::Grammar::statement is a ResizablePMCArray (size:1) but I am not sure how to reflect that in PIR or if that is even significant here. Underneath that are the linenumber and statement_type rules but I cannot seem to access them at all. I apologize in advance if this is something simple but any help would be greatly appreciated.
If you can have more than one element in the statement array (I expect you can) in the rule for Basic64::Grammar::statements, you need to grab the array, and iterate over it, calling tree.'get' on each element of the array. As an example, take a look at the PunieGrammar::lineseq rule in languages/punie/lib/ASTGrammar.tg.
If you can only ever have one statement (unlikely, but I mention it in case it's useful for other rules), then you can just grab the first item in the array (e.g. "cnode[0]") and pass that to tree.'get'.
(And thanks for the details you provided with the question. They made it easy to see the answer.)
Allison
