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From: xiaoyu xu <zhu...@gm...> - 2010-06-22 03:09:45
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Hi everyone, I met an exception when I "set_fixity "divides" (Infixr 450)" I checked the exception. It said Exception raised at Parse.add_rule: Grammer error: Attempt to have differently associated infixes (RIGHT and NONASSOC) at same level(450) I looked into the kananaskis-5-reference, I found that I couldn't define an infix at this level, because this was where other notation was. I solved it, use "set_fixity "divides" (Infixr 451)" or "set_fixity "divides" (Infix(NONASSOC, 450))" instead. My questions are: 1.what are the differences between (Infixr 450) and (Infix(NONASSOC, 450))? Which file introduces this? 2.How can I know at which level I can define an infix, at which I can't? 3.Should I clear the definitions after my work, how can I clear that? Thank you very much! |