function(result,exp){
                switch(exp.op){
                    case '<':
                    case '<=':
                        result.lower = exp;
                    break;
                    case '>':
                    case '>=':
                        result.upper = exp;
                    break;
                    case '=':
                    case '==':
                        result.midle = exp;
                    break;
                }
                delete exp.op;
            }
function(result,exp){
                switch(exp.op){
                    case '<':
                    case '<=':
                        result.lower = exp;
                    break;
                    case '>':
                    case '>=':
                        result.upper = exp;
                    break;
                    case '=':
                    case '==':
                        result.midle = exp;
                    break;
                }
                delete exp.op;
            }
function ( result , exp ) { switch ( exp . op ) { case '<' : case '<=' : result . lower = exp ; break ; case '>' : case '>=' : result . upper = exp ; break ; case '=' : case '==' : result . midle = exp ; break ; } delete exp . op ; }
for 2.0a<= or 2.0a= or 2.0a>=
for 2 . 0a< = or 2 . 0a = or 2 . 0a > =