Fix Many looping forever when inner parser succeeds without advancing - #93
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Many's loop assumed the inner parser would either advance or fail. Not and Option both return zero-advance successes (Skipped and NotPresent respectively) when their inner parser doesn't match, which left the loop state identical on every iteration. In tree mode, Option inside Many also caused unbounded memory growth: NotPresent is an ASTChild, so each iteration pushed it into the AST node. Both loops now break when the inner parser succeeds without consuming any input. Closes #92
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Many's loop assumed the inner parser would either advance or fail. Not and Option both return zero-advance successes (Skipped and NotPresent respectively) when their inner parser doesn't match, which left the loop state identical on every iteration.
In tree mode, Option inside Many also caused unbounded memory growth: NotPresent is an ASTChild, so each iteration pushed it into the AST node.
Both loops now break when the inner parser succeeds without consuming any input.
Closes #92