static/js/org/cytoscape.js
function( selector ){
      var eles = this;
      var fNodes = [];

      for( var i = 0; i < eles.length; i++ ){
        var ele = eles[i];
        var eleId = ele.id();

        if( !ele.isNode() ){ continue; }

        var edges = ele._private.edges;
        for( var j = 0; j < edges.length; j++ ){
          var edge = edges[j];
          var srcId = edge._private.data.source;
          var tgtId = edge._private.data.target;

          if( srcId === eleId && tgtId !== eleId ){
            fNodes.push( edge.target()[0] );
          }
        }
      }

      return new $$.Collection( this._private.cy, fNodes ).filter( selector );
    }
function( selector ){
      var eles = this;
      var fNodes = [];

      for( var i = 0; i < eles.length; i++ ){
        var ele = eles[i];
        var eleId = ele.id();

        if( !ele.isNode() ){ continue; }

        var edges = ele._private.edges;
        for( var j = 0; j < edges.length; j++ ){
          var edge = edges[j];
          var srcId = edge._private.data.source;
          var tgtId = edge._private.data.target;

          if( srcId === eleId && tgtId !== eleId ){
            fNodes.push( edge.target()[0] );
          }
        }
      }

      return new $$.Collection( this._private.cy, fNodes ).filter( selector );
    }
function ( selector ) { var eles = this ; var fNodes = [ ] ; for ( var i = 0 ; i < eles . length ; i ++ ) { var ele = eles [ i ] ; var eleId = ele . id ( ) ; if ( ! ele . isNode ( ) ) { continue ; } var edges = ele . _private . edges ; for ( var j = 0 ; j < edges . length ; j ++ ) { var edge = edges [ j ] ; var srcId = edge . _private . data . source ; var tgtId = edge . _private . data . target ; if ( srcId === eleId && tgtId !== eleId ) { fNodes . push ( edge . target ( ) [ 0 ] ) ; } } } return new $$ . Collection ( this . _private . cy , fNodes ) . filter ( selector ) ; }
normally called children in graph theory these nodes =edges=> forward nodes
normally called children in graph theory these nodes = edges = > forward nodes