1: <?php
 2: namespace Pharborist;
 3: 
 4: interface ParentNodeInterface extends NodeInterface {
 5:   /**
 6:    * Get the number of children.
 7:    * @return int
 8:    */
 9:   public function childCount();
10: 
11:   /**
12:    * Return the first child.
13:    * @return Node
14:    */
15:   public function firstChild();
16: 
17:   /**
18:    * Return the last child.
19:    * @return Node
20:    */
21:   public function lastChild();
22: 
23:   /**
24:    * Get the immediate children of this node.
25:    * @param callable $callback An optional callback to filter by.
26:    * @return NodeCollection
27:    */
28:   public function children(callable $callback = NULL);
29: 
30:   /**
31:    * Remove all child nodes.
32:    */
33:   public function clear();
34: 
35:   /**
36:    * Prepend nodes to this node.
37:    * @param Node|Node[]|NodeCollection $nodes
38:    * @return $this
39:    * @throws \InvalidArgumentException
40:    */
41:   public function prepend($nodes);
42: 
43:   /**
44:    * Append nodes to this node.
45:    * @param Node|Node[]|NodeCollection $nodes
46:    * @return $this
47:    * @throws \InvalidArgumentException
48:    */
49:   public function append($nodes);
50: 
51:   /**
52:    * Get the first (i.e. leftmost leaf) token.
53:    * @return TokenNode
54:    */
55:   public function firstToken();
56: 
57:   /**
58:    * Get the last (i.e. rightmost leaf) token.
59:    * @return TokenNode
60:    */
61:   public function lastToken();
62: 
63:   /**
64:    * Test if the node has a descendant that matches.
65:    * @param callable $callback Callback to test for match.
66:    * @return NodeCollection
67:    */
68:   public function has(callable $callback);
69: 
70:   /**
71:    * Test if the node is a descendant of this node.
72:    * @param Node $node Node to test
73:    * @return boolean
74:    */
75:   public function isDescendant(Node $node);
76: 
77:   /**
78:    * Find descendants that pass filter callback.
79:    * @param callable $callback Callback to filter by.
80:    * @return NodeCollection
81:    */
82:   public function find(callable $callback);
83: 
84:   /**
85:    * Perform callback on this node and all descendant nodes.
86:    * @param callable $callback Callback for each node.
87:    */
88:   public function walk(callable $callback);
89: }
90: