On Sun, Feb 24, 2013 at 6:31 AM, Martin Drautzburg wrote: Just a silly quick question: why isn't right-recursion a similar problem? Very roughly:
Left recursion is: let foo n = n + foo n in ...
Right recursion is: let foo 1 = 1; foo n = n + foo (n - 1) in ...
In short, matching the tokens before the right recursion will constitute an
end condition that will stop infinite recursion --- if only because you'll
hit the end of the input. Left recursion doesn't consume anything, just
re-executes itself.
--
brandon s allbery kf8nh sine nomine associates
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