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backend/vendor/doctrine/collections/src/Expr/ExpressionVisitor.php

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+<?php
+
+declare(strict_types=1);
+
+namespace Doctrine\Common\Collections\Expr;
+
+/**
+ * An Expression visitor walks a graph of expressions and turns them into a
+ * query for the underlying implementation.
+ */
+abstract class ExpressionVisitor
+{
+    /**
+     * Converts a comparison expression into the target query language output.
+     *
+     * @return mixed
+     */
+    abstract public function walkComparison(Comparison $comparison);
+
+    /**
+     * Converts a value expression into the target query language part.
+     *
+     * @return mixed
+     */
+    abstract public function walkValue(Value $value);
+
+    /**
+     * Converts a composite expression into the target query language output.
+     *
+     * @return mixed
+     */
+    abstract public function walkCompositeExpression(CompositeExpression $expr);
+
+    /**
+     * Dispatches walking an expression to the appropriate handler.
+     *
+     * @return mixed
+     */
+    public function dispatch(Expression $expr)
+    {
+        return $expr->visit($this);
+    }
+}