--- title: "Changelog 4.x" manual: "Fluid Explained" version: "main" permalink: "https://docs.typo3.org/permalink/fluid:changelog-4-x" source: "Changelog/4.x.rst" rendered: "2026-09-26T08:24:58+00:00" --- # Changelog 4.x {#changelog-4-x} This Changelog lists notable deprecation and breaking changes. The full list of changes is available [in the Fluid releases on GitHub](https://github.com/TYPO3/Fluid/releases). ## 4.5 {#4-5} - Deprecation: Using the `xmlns` namespace syntax with a PHP namespace instead of an url is deprecated and will no longer work in Fluid v5. - Deprecation: Method `TYPO3FluidFluidCoreViewHelperAbstractViewHelper::validateArguments()` has been marked as deprecated and will be removed in Fluid v5. - Deprecation: Custom implementations of the `validateArguments()` methods in ViewHelpers will no longer be called in Fluid v5. Use `TYPO3FluidFluidCoreViewHelperViewHelperArgumentsValidatedEventInterface` instead. - - **Deprecation: Classes, interfaces, methods and constants related to cache warmup are deprecated and will be removed in Fluid v5:** - `TYPO3FluidFluidCoreCacheFluidCacheInterface::getCacheWarmer()` - `TYPO3FluidFluidCoreCacheSimpleFileCache::getCacheWarmer()` - `TYPO3FluidFluidCoreCacheFluidCacheWarmerInterface` - `TYPO3FluidFluidCoreCacheStandardCacheWarmer` - `TYPO3FluidFluidCoreCacheFluidCacheWarmupResult` - `TYPO3FluidFluidCoreCompilerFailedCompilingState` - `TYPO3FluidFluidCoreCompilerTemplateCompiler::MODE_NORMAL` - `TYPO3FluidFluidCoreCompilerTemplateCompiler::MODE_WARMUP` - `TYPO3FluidFluidCoreCompilerTemplateCompiler::$mode` - `TYPO3FluidFluidCoreCompilerTemplateCompiler::enterWarmupMode()` - `TYPO3FluidFluidCoreCompilerTemplateCompiler::isWarmupMode()` - Deprecation: The `` ViewHelper is deprecated and will be removed in Fluid v5. - Deprecation: Fluid variable names can no longer start with an underscore character (`_`). Adding such a variable to a template now emits a E_USER_DEPRECATED level error and will result in an exception in Fluid v5. Note that this doesn't affect array keys or object property names, only the name of the variable itself. - Deprecation: Replacing `` sections by empty lines is deprecated and will be removed in Fluid v5. Method `TYPO3FluidFluidCoreParserTemplateProcessorNamespaceDetectionTemplateProcessor.php::replaceCdataSectionsByEmptyLines()` now emits a E_USER_DEPRECATED level error. ## 4.4 {#4-4} - Deprecation: Setting a template's layout with the variable `layoutName` is deprecated and will no longer work in Fluid v5. Use `TYPO3FluidFluidCoreParserParsingState->setLayoutName()` instead. - Deprecation: Constant `TYPO3FluidFluidCoreCompilerTemplateCompiler::LAYOUT_VARIABLE` has been marked as deprecated and will be removed in Fluid v5. ## 4.3 {#4-3} - Deprecation: Property `TYPO3FluidFluidCoreViewHelperAbstractViewHelper::$childNodes` has been marked as deprecated and will be removed in Fluid v5. Use `$viewHelperNode->getChildNodes()` instead. - Deprecation: Method `TYPO3FluidFluidCoreViewHelperAbstractViewHelper::setChildNodes()` has been marked as deprecated and will be removed in Fluid v5. - Deprecation: Method `TYPO3FluidFluidCoreViewHelperViewHelperInterface::setChildNodes()` has been marked as deprecated and will be removed in Fluid v5. ## 4.2 {#4-2} - Deprecation: Method `TYPO3FluidFluidCoreViewHelperViewHelperResolver::resolvePhpNamespaceFromFluidNamespace()` now emits a E_USER_DEPRECATED level error. - Deprecation: Method `TYPO3FluidFluidCoreViewHelperViewHelperResolver::isNamespaceValidOrIgnored()` now emits a E_USER_DEPRECATED level error. - Deprecation: Constant `TYPO3FluidFluidCoreParserPatterns::NAMESPACESUFFIX` has been marked as deprecated and will be removed in Fluid v5. - Deprecation: Method `TYPO3FluidFluidCoreViewHelperAbstractViewHelper::isValidType()` now emits a E_USER_DEPRECATED level error. - Deprecation: Method `TYPO3FluidFluidCoreViewHelperAbstractViewHelper::getFirstElementOfNonEmpty()` now emits a E_USER_DEPRECATED level error. - Deprecation: Method `TYPO3FluidFluidCoreViewHelperAbstractViewHelper::postParseEvent()` now emits a E_USER_DEPRECATED level error. It will be removed with Fluid v5. ViewHelpers using this event should switch to the new `TYPO3FluidFluidCoreViewHelperViewHelperNodeInitializedEventInterface` - Deprecation: Method `TYPO3FluidFluidCoreViewHelperViewHelperResolver::addNamespaces()` now emits a E_USER_DEPRECATED level error. - Deprecation: Inheritance of ViewHelper namespaces is deprecated. If a ViewHelper namespace is used in a template that is neither defined globally nor locally directly in the template, Fluid now emits a E_USER_DEPRECATED level error. ## 4.0 {#4-0} - Breaking: Method `TYPO3FluidFluidViewAbstractTemplateView::initializeRenderingContext()` has been removed. - Breaking: Method `TYPO3FluidFluidViewAbstractTemplateView::setCache()` has been removed. - Breaking: Method `TYPO3FluidFluidViewAbstractTemplateView::getTemplatePaths()` has been removed. - Breaking: Method `TYPO3FluidFluidViewAbstractTemplateView::getViewHelperResolver()` has been removed. - Breaking: Change visibility of class constants that represent internal Fluid state. The following constants have been set to `protected` and can only be accessed by `AbstractTemplateView` and its child implementations: `TYPO3FluidFluidViewAbstractTemplateView::RENDERING_TEMPLATE`, `TYPO3FluidFluidViewAbstractTemplateView::RENDERING_PARTIAL`, `TYPO3FluidFluidViewAbstractTemplateView::RENDERING_LAYOUT` - Breaking: Careful addition of method and property type hints throughout the system. This should be only mildly breaking and projects should be able to adapt easily. - Deprecation: First parameter of method `TYPO3FluidFluidViewTemplatePaths->__construct()` is deprecated. The Constructor will be removed with Fluid v5. - Deprecation: Method `TYPO3FluidFluidViewTemplatePaths->fillFromConfigurationArray()` now emits a E_USER_DEPRECATED level error. - Deprecation: Method `TYPO3FluidFluidViewTemplatePaths->fillDefaultsByPackageName()` now emits a E_USER_DEPRECATED level error. - Deprecation: Method `TYPO3FluidFluidViewTemplatePaths->ensureAbsolutePaths()` now emits a E_USER_DEPRECATED level error. - Deprecation: Method `TYPO3FluidFluidViewTemplatePaths->extractPathArrays()` now emits a E_USER_DEPRECATED level error. - Deprecation: Method `TYPO3FluidFluidViewTemplatePaths->getPackagePath()` now emits a E_USER_DEPRECATED level error. - Deprecation: Method `TYPO3FluidFluidViewTemplatePaths->toArray()` now emits a E_USER_DEPRECATED level error. - Deprecation: Constant `TYPO3FluidFluidViewTemplatePaths::DEFAULT_TEMPLATES_DIRECTORY` has been marked as deprecated and will be removed in Fluid v5. - Deprecation: Constant `TYPO3FluidFluidViewTemplatePaths::DEFAULT_LAYOUTS_DIRECTORY` has been marked as deprecated and will be removed in Fluid v5. - Deprecation: Constant `TYPO3FluidFluidViewTemplatePaths::DEFAULT_PARTIALS_DIRECTORY` has been marked as deprecated and will be removed in Fluid v5. - Deprecation: Trait `TYPO3FluidFluidCoreViewHelperTraitsCompileWithRenderStatic` now emits a E_USER_DEPRECATED level error. - Deprecation: Trait `TYPO3FluidFluidCoreViewHelperTraitsCompileWithContentArgumentAndRenderStatic` now emits a E_USER_DEPRECATED level error. - Deprecation: Static method `renderStatic()` on ViewHelpers that don't use `TYPO3FluidFluidCoreViewHelperTraitsCompileWithRenderStatic` or `TYPO3FluidFluidCoreViewHelperTraitsCompileWithContentArgumentAndRenderStatic` now emits a E_USER_DEPRECATED level error. - Deprecation: Method `TYPO3FluidFluidCoreViewHelperAbstractViewHelper->overrideArgument()` now emits a E_USER_DEPRECATED level error. - Deprecation: Calling method `TYPO3FluidFluidCoreViewHelperAbstractTagBasedViewHelper->registerUniversalTagAttributes()` now emits a E_USER_DEPRECATED level error. - Deprecation: Calling method `TYPO3FluidFluidCoreViewHelperAbstractTagBasedViewHelper->registerTagAttribute()` now emits a E_USER_DEPRECATED level error. - Breaking: Method `TYPO3FluidFluidCoreViewHelperAbstractConditionViewHelper->evaluateCondition()` and handling has been removed. - Breaking: Method `TYPO3FluidFluidCoreParserSyntaxTreeObjectAccessorNode->getAccessors()` has been removed. - Breaking: Constant `TYPO3FluidFluidCoreCompilerTemplateCompiler::SHOULD_GENERATE_VIEWHELPER_INVOCATION` has been removed. - Breaking: Constant `TYPO3FluidFluidCoreVariablesStandardVariableProvider::ACCESSOR_ARRAY` has been removed. - Breaking: Constant `TYPO3FluidFluidCoreVariablesStandardVariableProvider::ACCESSOR_GETTER` has been removed. - Breaking: Constant `TYPO3FluidFluidCoreVariablesStandardVariableProvider::ACCESSOR_ASSERTER` has been removed. - Breaking: Constant `TYPO3FluidFluidCoreVariablesStandardVariableProvider::ACCESSOR_PUBLICPROPERTY` has been removed. - Breaking: Static property `TYPO3FluidFluidCoreParserPatterns::$SCAN_PATTERN_ESCAPINGMODIFIER` has been removed. - Breaking: Trait `TYPO3FluidFluidCoreViewHelperTraitsParserRuntimeOnly` has been removed. - Breaking: Interface `TYPO3FluidFluidCoreParserSyntaxTreeExpressionParseTimeEvaluatedExpressionNodeInterface` and its handling has been removed. - Breaking: Class `TYPO3FluidFluidCoreVariablesVariableExtractor` has been removed. - Breaking: Class `TYPO3FluidFluidCoreCompilerViewHelperCompiler` has been removed. - Breaking: Exception `TYPO3FluidFluidCoreCompilerStopCompilingChildrenException` and its handling has been removed. - Breaking: Test abstracts `TYPO3FluidFluidTestsBaseTestCase` and `TYPO3FluidFluidTestsUnitTestCase` have been removed. - Breaking: Using invalid namespace `https://typo3.org` instead of `http://typo3.org` (https vs. http) throws an exception - Important: Minimum PHP version has been raised to ^8.2