Fix issue with truncated output from warn() when running in narwhal-jsc. Narwhal-jsc's print() function doesn't accept multiple arguments.
Fix issue with truncated output from warn() when running in narwhal-jsc. Narwhal-jsc's print() function doesn't accept multiple arguments.

GerHobbelt/jison,GerHobbelt/jison,GerHobbelt/jison,GerHobbelt/jison