if foo.something foo.instance_eval "SYNTAX ERROR" end I know any form of eval is sort of cheating... But perhaps what he meant was not a syntax erro

if foo.something foo.instance_eval "SYNTAX ERROR" end I know any form of eval is sort of cheating... But perhaps what he meant was not a syntax error, but things like: if foo.something foo.something_misspelled = bar end Which isn't technically a syntax error, but that code is invalid in a statically typed language.