grammar = p:production _ g:grammar _ 
{return p+"<br>"+g } / production _

production = pre: nonterminal seta pos: char* {return pre[0]+" ::= " + pos.join("").fontcolor("green");}

seta="->" {return "&gt;";}

nonterminal = capital letter*

terminal = letter+

word = char+ {return text();}

char = letter / capital

capital = [A-Z]

letter = [a-z]

_ "whitespace"
  = [ \t\n\r]*