Fix non-associativity of non-eq comparison ops in LL1 grammar #4
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This patch only fixes PA1B. Although PA1A specifies that '<=' is nonassoc, we can still write Maybe we just accept that, and let the subsequent semantic analysis do the job? |
Hoblovski
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Non-equal comparison operators such as <, >, ge, le come without associativity, yet current LL(1) grammar treats them as left associative, which can bring about erroneous parsing output when handling
a < b < c(this form should have triggered a syntax error)