module Parser module Keywords include Parslet rule(:keyword_begin) { str('begin').as(:begin) >> space?} rule(:keyword_class) { str('class') >> space? } rule(:keyword_else) { str('else').as(:else) >> space? } rule(:keyword_end) { str('end').as(:end) >> space? } rule(:keyword_false) { str('false').as(:false) } rule(:keyword_field) { str('field').as(:field) >> space? } rule(:keyword_return) { str('return').as(:return) >> space?} rule(:keyword_true) { str('true').as(:true) } rule(:keyword_nil) { str('nil').as(:nil) } # this rule is just to make sure identifiers can't be keywords. Kind of duplication here, but we need the # space in above rules, so just make sure to add any here too. rule(:keyword){ str('if_') | str('else') | str('end') | str('while_') | str('false') | str('true')| str('nil') | str("class") | str('return')| str('int')| str('field')} end end