Parsing Complex Comparisons

An interesting tidbit: can your programming language parse a < b < c? Perl can’t. Ruby can, but returns an error “undefined method `>’ for false:FalseClass.” Interestingly, Python accepts it, and even gives the correct result. Something clever must be going on in the parser to make that work.

Update October 17: Although Lisp can’t parse the expression directly, it does correctly handle the equivalent S-expression (< a b c).

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