Merge pull request #12 from CrimsonNynja/minor-update

changed callable syntax to php 7

Author: CrimsonNynja

src/PhpTrees/BinaryHeap.php

@@ -182,7 +182,7 @@ private function bubbleUp(int $index) : void
         $parentIndex = (int)($index - 1) / 2;
 
         if ($this->comparator !== null) {
-            if ($this->comparator->__invoke($this->heap[$parentIndex], $this->heap[$index])) {
+            if (($this->comparator)($this->heap[$parentIndex], $this->heap[$index])) {
                 $dummy = $this->heap[$parentIndex];
                 $this->heap[$parentIndex] = $this->heap[$index];
                 $this->heap[$index] = $dummy;
@@ -218,7 +218,7 @@ private function bubbleDown(int $index) : void
         $minIndex = $index;
 
         if ($this->comparator !== null) {
-            if ($this->comparator->__invoke($this->heap[$index], $this->heap[$leftIndex])) {
+            if (($this->comparator)($this->heap[$index], $this->heap[$leftIndex])) {
                 $minIndex = $leftIndex;
             }
         }
@@ -230,7 +230,7 @@ private function bubbleDown(int $index) : void
 
         if (($rightIndex < $length)) {
             if ($this->comparator !== null) {
-                if ($this->comparator->__invoke($this->heap[$minIndex], $this->heap[$rightIndex])) {
+                if (($this->comparator)($this->heap[$minIndex], $this->heap[$rightIndex])) {
                     $minIndex = $rightIndex;
                 }
             }

src/PhpTrees/BinarySearchTree.php

@@ -139,7 +139,7 @@ public function find($value, BstNode $node = null) : ?BstNode
      */
     private function findComparator($value, BstNode $node = null) : ?BstNode
     {
-        $cmp = $this->comparator->__invoke($node->getValue(), $value);
+        $cmp = ($this->comparator)($node->getValue(), $value);
         if ($cmp === true && $node->getRightChild() !== null) {
             return $this->find($value, $node->getRightChild());
         }

src/PhpTrees/BstNode.php

@@ -77,7 +77,7 @@ public function addChild($value) : void
      */
     private function addChildComparator($value) : void
     {
-        $cmp = $this->comparator->__invoke($this->value, $value);
+        $cmp = ($this->comparator)($this->value, $value);
         if ($cmp === true) {
             if ($this->right === null) {
                 $this->right = new BstNode($value, $this);