src/model/vizmapper.js
/**
   * Set or get the global edge style for a property
   * @param {String} property The property name
   * @param {StyleStruct} [value] When specified, the style is set to this value.  When unspecified, the current value is returned.
   * @returns {StyleStruct} The current style (when `value` is unspecified)
   */
Set or get the global edge style for a property
@param {String} property The property name
@param {StyleStruct} [value] When specified, the style is set to this value.  When unspecified, the current value is returned.
@returns {StyleStruct} The current style (when `value` is unspecified)
Set or get the global edge style for a property @param { String } property The property name @param { StyleStruct } [ value ] When specified the style is set to this value . When unspecified the current value is returned . @returns { StyleStruct } The current style ( when ` value ` is unspecified )
edge(property, value){
    if(value){
      this.set(EDGE_SELECTOR, property, value);
    } else {
      return this.get(EDGE_SELECTOR, property);
    }
  }
edge ( property , value ) { if ( value ) { this . set ( EDGE_SELECTOR , property , value ) ; } else { return this . get ( EDGE_SELECTOR , property ) ; } }
Set or get the global edge style for a property
 @param {String} property The property name
 @param {StyleStruct} [value] When specified, the style is set to this value.
Set or get the global edge style for a property @param { String } property The property name @param { StyleStruct } [ value ] When specified the style is set to this value .