lib/collection/property-list.js
function (item) {
        return this.members.indexOf(_.isString(item) ? (item = this.one(item)) : item);
    }
function (item) {
        return this.members.indexOf(_.isString(item) ? (item = this.one(item)) : item);
    }
function ( item ) { return this . members . indexOf ( _ . isString ( item ) ? ( item = this . one ( item ) ) : item ) ; }
Find the index of an item in this list

@param {String|Object} item
@returns {Number}
Find the index of an item in this list