Added Non-Associative associativity for Pratt Parsers. #600
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In current Pratt parsers, only associativity type of
left
andright
are supported. However, according to the original designs of Pratt parsing, it should also support Non-Associative infix binary operators.For example, consider operators
==
as a non-associative operator. We should be able to identify it as non-associative and therefore rejecting1 == 2 == 3
as an expression with the numbers being atomic literals. Whilst the current design only allow==
to be either left-associative or right-associative.This PR added associativity
non
for infix binary operators, and changed the binding power calculation function slightly based on The Original Parsing Methodology and this article.