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typo3conf/ext/vhs/Classes/ViewHelpers/Variable/SetViewHelper.php

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+<?php
+namespace FluidTYPO3\Vhs\ViewHelpers\Variable;
+
+/*
+ * This file is part of the FluidTYPO3/Vhs project under GPLv2 or later.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.md file that was distributed with this source code.
+ */
+
+use TYPO3\CMS\Extbase\Reflection\ObjectAccess;
+use TYPO3\CMS\Fluid\Core\ViewHelper\AbstractViewHelper;
+
+/**
+ * ### Variable: Set
+ *
+ * Sets a single variable in the TemplateVariableContainer
+ * scope. The variable then becomes accessible as {var}.
+ *
+ * Combines well with `v:variable.get` to set shorter variable
+ * names referencing dynamic variables, such as:
+ *
+ *     <v:variable.set name="myObject" value="{v:variable.get(name: 'arrayVariable.{offset}')}" />
+ *     <!-- If {index} == 4 then {myObject} is now == {arrayVariable.4} -->
+ *     {myObject.name} <!-- corresponds to {arrayVariable.4.name} -->
+ *
+ * Note that `{arrayVariable.{offset}.name}` is not possible
+ * due to the way Fluid parses nodes; the above piece of
+ * code would try reading `arrayVariable.{offset}.name`
+ * as a variable actually called "arrayVariable.{offset}.name"
+ * rather than the correct `arrayVariable[offset][name]`.
+ *
+ * In many ways this ViewHelper works like `f:alias`
+ * with one exception: in `f:alias` the variable only
+ * becomes accessible in the tag content, whereas `v:variable.set`
+ * inserts the variable in the template and leaves it there
+ * (it "leaks" the variable).
+ *
+ * If $name contains a dot, VHS will attempt to load the object
+ * stored under the named used as the first segment part and
+ * set the value at the remaining path. E.g.
+ * `{value -> v:variable.set(name: 'object.property.subProperty')}`
+ * would attempt to load `{object}` first, then set
+ * `property.subProperty` on that object/array using
+ * ObjectAccess::setPropertyPath(). If `{object}` is not
+ * an object or an array, the variable will not be set. Please
+ * note: Extbase does not currently support setting variables
+ * deeper than two levels, meaning a `name` of fx `foo.bar.baz`
+ * will be ignored. To set values deeper than two levels you
+ * must first extract the second-level object then set the
+ * value on that object.
+ *
+ * Using as `{value -> v:variable.set(name: 'myVar')}` makes `{myVar}` contain
+ * `{value}`.
+ *
+ * @author Claus Due <claus@namelesscoder.net>
+ * @package Vhs
+ * @subpackage ViewHelpers\Var
+ */
+class SetViewHelper extends AbstractViewHelper {
+
+	/**
+	 * Set (override) the variable in $name.
+	 *
+	 * @param string $name
+	 * @param mixed $value
+	 * @return void
+	 */
+	public function render($name, $value = NULL) {
+		if (NULL === $value) {
+			$value = $this->renderChildren();
+		}
+		if (FALSE === strpos($name, '.')) {
+			if (TRUE === $this->templateVariableContainer->exists($name)) {
+				$this->templateVariableContainer->remove($name);
+			}
+			$this->templateVariableContainer->add($name, $value);
+		} elseif (1 === substr_count($name, '.')) {
+			$parts = explode('.', $name);
+			$objectName = array_shift($parts);
+			$path = implode('.', $parts);
+			if (FALSE === $this->templateVariableContainer->exists($objectName)) {
+				return NULL;
+			}
+			$object = $this->templateVariableContainer->get($objectName);
+			try {
+				ObjectAccess::setProperty($object, $path, $value);
+				// Note: re-insert the variable to ensure unreferenced values like arrays also get updated
+				$this->templateVariableContainer->remove($objectName);
+				$this->templateVariableContainer->add($objectName, $object);
+			} catch (\Exception $error) {
+				return NULL;
+			}
+		}
+		return NULL;
+	}
+
+}