nearley-math-parser

@{%
  const flatten = d => {
    return d.reduce(
      (a, b) => {
        return a.concat(b);
      },
      []
    );
  };

	const filter = d => {
    return d.filter((token) => {
      return token !== null;
    });
  };
%}


APP -> MULTPERC {% (a) => `(${ a.join('') }) * 100`%}
  | ADDPERC  {% (a) => flatten(a).join('') %}

ADDPERC -> ADD _ [-+] _ PERC {% (a) => `${a[0]} ${a[2]} ${a[4]} * (${a[0]})`%}

ADD -> ADD _ [+-] _ INT {% (a) => a.join('') %}
	| INT

MULTPERC -> MULTPERC _ "/" _ PERC {% (a) => `${a.join(' ')}` %}
		  | MULTPERC _ "*" _ PERC {% (a) => `${a.join(' ')}` %}
      | PERC

PERC -> INT "%" {% (p) => {
	return `${p[0]}/100`;
} %}

INT -> [0-9]:+ {%
	(d) => {
		return `${d[0].join('')}`
	}
%}

_ -> [\s]:* {% function(d) {return null } %}