diff --git a/CHANGELOG.md b/CHANGELOG.md
index f499de13..918783ff 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,12 @@
 
 ## [Unreleased][unreleased]
 
+### Added
+- Support for form fields in containers
+
+### Fixed
+- Report errors when numeric container names are used in latte
+
 ## [0.13.0] - 2023-06-05
 ### Changed
 - Separated collection of Form Containers
diff --git a/docs/how_it_works.md b/docs/how_it_works.md
index 62d00856..4d87a126 100644
--- a/docs/how_it_works.md
+++ b/docs/how_it_works.md
@@ -125,10 +125,95 @@ It is important to check the context first (text after path of latte file - rend
 
     Now the type of `$baz` will be `'bar'|null` and isset() in condition will be valid.
 
-<!-- TODO
+
 ## Components
--->
 
-<!-- TODO
+Components are collected from PHP classes (e.g. Presenters or Controls) when using one of these ways:
+
+1) class method createComponent()
+```php
+protected function createComponentSomething(): SomeControl
+{
+    return new SomeControl();
+}
+```
+ 
+2) calling method addComponent()
+```php
+public function actionDefault(): void
+{
+    $this->addComponent('something', new SomeControl());
+}
+```
+
+3) assign to $this:
+```php
+public function actionDefault(): void
+{
+    $this['something'] = new SomeControl();
+}
+```
+
+Subcomponents of components are also collected, so it is possible to use this:
+```latte
+{control someControl}
+{control someControl-header}
+{control someControl-body}
+```
+
+### Common errors
+
+#### Component with name "xxx" probably doesn't exist.
+First of all, check if your component is registered in Presenter / Control using one of way described above and if the name fits.
+
+
 ## Forms
--->
+
+Forms are collected from PHP classes (e.g. Presenters or Controls) when they are registered as components via `createComponent*` or `createComponent` method if this method returns instance of `Nette\Forms\Form`.
+Form fields and form containers are also collected and can be then analysed.
+
+**IMPORTANT NOTE**: Container fields are currently assigned to containers if the name of container is the same as the name of variable which adds some field to this container.  
+
+### Common errors
+
+#### Form control with name "xxx" probably does not exist.
+Let's say you register form like this:
+
+```php
+
+use Nette\Application\UI\Form;
+
+protected function createComponentContainerForm(): Form
+{
+    $form = new Form();
+    $form->setMethod('get');
+    $form->addCheckbox('checkbox', 'Checkbox');
+    $part1 = $form->addContainer('part1');
+    $part1->addText('text1', 'Text 1');
+    $part1->addSubmit('submit1', 'Submit 1');
+
+    $part2 = $form->addContainer('part2');
+    $part2->addText('text2', 'Text 2');
+    $part2->addSubmit('submit2', 'Submit 2');
+
+    return $form;
+}
+```
+
+
+
+Then you can access all registered fields in latte this way:
+```latte
+{form containerForm}
+    {$form[part1][text1]->getHtmlId()}
+    {input part1-text1}
+    {input part1-submit1}
+
+    {input part2-text2}
+    {input part2-submit2}
+
+    {input checkbox:}
+
+    {input xxx} <-- this field is not registered in createComponent method therefore it is marked as non-existing 
+{/form}
+```
diff --git a/src/Compiler/NodeVisitor/AddFormClassesNodeVisitor.php b/src/Compiler/NodeVisitor/AddFormClassesNodeVisitor.php
index b531b782..91fef295 100644
--- a/src/Compiler/NodeVisitor/AddFormClassesNodeVisitor.php
+++ b/src/Compiler/NodeVisitor/AddFormClassesNodeVisitor.php
@@ -134,11 +134,8 @@ public function enterNode(Node $node): ?Node
                     $itemArgument = $node->getArgs()[0] ?? null;
                     $itemArgumentValue = $itemArgument ? $itemArgument->value : null;
 
-                    if ($itemArgumentValue instanceof String_) {
-                        $controlName = $itemArgumentValue->value;
-                        // TODO remove when container are supported
-                        $controlNameParts = explode('-', $controlName);
-                        $controlName = end($controlNameParts);
+                    if ($itemArgumentValue instanceof String_ || $itemArgumentValue instanceof LNumber) {
+                        $controlName = (string)$itemArgumentValue->value;
                         $formControl = $this->actualForm->getControl($controlName);
                         if ($formControl === null) {
                             $this->errorControlNodes[] = [
@@ -178,11 +175,8 @@ public function enterNode(Node $node): ?Node
                 return null;
             }
 
-            if ($node->dim instanceof String_) {
-                $controlName = $node->dim->value;
-                // TODO remove when container are supported
-                $controlNameParts = explode('-', $controlName);
-                $controlName = end($controlNameParts);
+            if ($node->dim instanceof String_ || $node->dim instanceof LNumber) {
+                $controlName = (string)$node->dim->value;
                 $formControl = $this->actualForm->getControl($controlName);
                 if ($formControl === null) {
                     $this->errorControlNodes[] = [
@@ -196,6 +190,29 @@ public function enterNode(Node $node): ?Node
                 if ($formControlType instanceof ObjectType && ($formControlType->isInstanceOf('Nette\Forms\Controls\CheckboxList')->yes() || $formControlType->isInstanceOf('Nette\Forms\Controls\RadioList')->yes())) {
                     $this->possibleAlwaysTrueLabels[] = $this->findParentStmt($node);
                 }
+
+                /**
+                 * Replace:
+                 * <code>
+                 * $form['foo-bar']->getControl();
+                 * </code>
+                 *
+                 * With:
+                 * <code>
+                 * $form['foo']['bar']->getControl();
+                 * <code>
+                 *
+                 * if foobar exists in actual form
+                 */
+                if (str_contains($controlName, '-')) {
+                    $controlNameParts = explode('-', $controlName);
+                    $tmpDim = new ArrayDimFetch(new Variable('form'), new String_(array_shift($controlNameParts)));
+                    foreach ($controlNameParts as $controlNamePart) {
+                        $tmpDim = new ArrayDimFetch($tmpDim, new String_($controlNamePart));
+                    }
+                    $tmpDim->setAttributes($node->getAttributes());
+                    return $tmpDim;
+                }
             } elseif ($node->dim instanceof Variable) {
                 // dynamic control
             } else {
diff --git a/src/LatteContext/CollectedData/Form/CollectedFormControl.php b/src/LatteContext/CollectedData/Form/CollectedFormControl.php
index 3cd30080..52615041 100644
--- a/src/LatteContext/CollectedData/Form/CollectedFormControl.php
+++ b/src/LatteContext/CollectedData/Form/CollectedFormControl.php
@@ -16,14 +16,17 @@ final class CollectedFormControl extends CollectedLatteContextObject
 
     private ControlInterface $formControl;
 
+    private string $parentName;
+
     /**
      * @param class-string $className
      */
-    public function __construct(string $className, string $methodName, ControlInterface $formControl)
+    public function __construct(string $className, string $methodName, ControlInterface $formControl, string $parentName)
     {
         $this->className = $className;
         $this->methodName = $methodName;
         $this->formControl = $formControl;
+        $this->parentName = $parentName;
     }
 
     public function getClassName(): string
@@ -40,4 +43,9 @@ public function getFormControl(): ControlInterface
     {
         return $this->formControl;
     }
+
+    public function getParentName(): string
+    {
+        return $this->parentName;
+    }
 }
diff --git a/src/LatteContext/Collector/FormControlCollector.php b/src/LatteContext/Collector/FormControlCollector.php
index 2ff580f8..74b80276 100644
--- a/src/LatteContext/Collector/FormControlCollector.php
+++ b/src/LatteContext/Collector/FormControlCollector.php
@@ -127,6 +127,7 @@ public function collectData(Node $node, Scope $scope): ?array
             return null;
         }
 
+        $parentName = $this->nameResolver->resolve($node->var) ?: 'form';
         $formControls = [];
         foreach ($controlNames as $controlName) {
             $controlName = (string)$controlName;
@@ -141,7 +142,8 @@ public function collectData(Node $node, Scope $scope): ?array
             $formControls[] = new CollectedFormControl(
                 $classReflection->getName(),
                 $methodName,
-                $formControl
+                $formControl,
+                $parentName
             );
         }
         return $formControls;
diff --git a/src/LatteContext/Finder/FormControlFinder.php b/src/LatteContext/Finder/FormControlFinder.php
index b5a40974..fc42c0a3 100644
--- a/src/LatteContext/Finder/FormControlFinder.php
+++ b/src/LatteContext/Finder/FormControlFinder.php
@@ -6,7 +6,9 @@
 
 use Efabrica\PHPStanLatte\Analyser\LatteContextData;
 use Efabrica\PHPStanLatte\LatteContext\CollectedData\Form\CollectedFormControl;
+use Efabrica\PHPStanLatte\Template\Form\Container;
 use Efabrica\PHPStanLatte\Template\Form\ControlInterface;
+use Efabrica\PHPStanLatte\Template\Form\Field;
 use Efabrica\PHPStanLatte\Template\ItemCombinator;
 use PHPStan\Reflection\ReflectionProvider;
 
@@ -28,14 +30,55 @@ public function __construct(LatteContextData $latteContext, ReflectionProvider $
 
         $collectedFormControls = $latteContext->getCollectedData(CollectedFormControl::class);
 
+        /** @var array<string, array<string, array<string, Container>>> $containers */
+        $containers = [];
+
+        /** @var array<string, array<string, array<string, Field[]>>> $controls */
+        $controls = [];
+
         /** @var CollectedFormControl $collectedFormControl */
         foreach ($collectedFormControls as $collectedFormControl) {
             $className = $collectedFormControl->getClassName();
             $methodName = $collectedFormControl->getMethodName();
-            if (!isset($this->assignedFormControls[$className][$methodName])) {
-                $this->assignedFormControls[$className][$methodName] = [];
+            $formControl = $collectedFormControl->getFormControl();
+            if (!$formControl instanceof Container) {
+                $parentName = $collectedFormControl->getParentName();
+                if (!isset($controls[$className][$methodName][$parentName])) {
+                    $controls[$className][$methodName][$parentName] = [];
+                }
+                $controls[$className][$methodName][$parentName][] = $formControl;
+                continue;
+            }
+
+            $containerName = $formControl->getName();
+            $containers[$className][$methodName][$containerName] = $formControl;
+        }
+
+        foreach ($containers as $className => $classContainers) {
+            foreach ($classContainers as $methodName => $methodContainers) {
+                foreach ($methodContainers as $containerName => $container) {
+                    $containerControls = $controls[$className][$methodName][$containerName] ?? [];
+                    $container->addControls($containerControls);
+                    unset($controls[$className][$methodName][$containerName]);
+
+                    if (!isset($this->assignedFormControls[$className][$methodName])) {
+                        $this->assignedFormControls[$className][$methodName] = [];
+                    }
+
+                    $this->assignedFormControls[$className][$methodName][] = $container;
+                }
+            }
+        }
+
+        foreach ($controls as $className => $classControls) {
+            foreach ($classControls as $methodName => $methodControls) {
+                foreach ($methodControls as $parentControls) {
+                    if (!isset($this->assignedFormControls[$className][$methodName])) {
+                        $this->assignedFormControls[$className][$methodName] = [];
+                    }
+                    $this->assignedFormControls[$className][$methodName] = array_merge($this->assignedFormControls[$className][$methodName], $parentControls);
+                }
             }
-            $this->assignedFormControls[$className][$methodName][] = $collectedFormControl->getFormControl();
         }
     }
 
diff --git a/src/Template/Form/Behavior/ControlHolderBehavior.php b/src/Template/Form/Behavior/ControlHolderBehavior.php
index be87d021..4ffa1989 100644
--- a/src/Template/Form/Behavior/ControlHolderBehavior.php
+++ b/src/Template/Form/Behavior/ControlHolderBehavior.php
@@ -4,6 +4,7 @@
 
 namespace Efabrica\PHPStanLatte\Template\Form\Behavior;
 
+use Efabrica\PHPStanLatte\Template\Form\ControlHolderInterface;
 use Efabrica\PHPStanLatte\Template\Form\ControlInterface;
 
 trait ControlHolderBehavior
@@ -21,13 +22,19 @@ public function getControls(): array
 
     public function getControl(string $name): ?ControlInterface
     {
-        return $this->controls[$name] ?? null;
+        $nameParts = explode('-', $name);
+        $controlName = array_shift($nameParts);
+        $control = $this->controls[$controlName] ?? null;
+        if ($control instanceof ControlHolderInterface && $nameParts !== []) {
+            return $control->getControl(implode('-', $nameParts));
+        }
+        return $control;
     }
 
     /**
      * @param ControlInterface[] $controls
      */
-    private function addControls(array $controls): void
+    public function addControls(array $controls): void
     {
         foreach ($controls as $control) {
             $this->controls[$control->getName()] = $control;
diff --git a/src/Template/Form/ControlHolderInterface.php b/src/Template/Form/ControlHolderInterface.php
index 34e72844..7f04ba52 100644
--- a/src/Template/Form/ControlHolderInterface.php
+++ b/src/Template/Form/ControlHolderInterface.php
@@ -10,4 +10,6 @@ interface ControlHolderInterface
      * @return ControlInterface[]
      */
     public function getControls(): array;
+
+    public function getControl(string $name): ?ControlInterface;
 }
diff --git a/tests/Rule/LatteTemplatesRule/PresenterWithoutModule/Fixtures/templates/Forms/default.latte b/tests/Rule/LatteTemplatesRule/PresenterWithoutModule/Fixtures/templates/Forms/default.latte
index c16759b9..4b03222c 100644
--- a/tests/Rule/LatteTemplatesRule/PresenterWithoutModule/Fixtures/templates/Forms/default.latte
+++ b/tests/Rule/LatteTemplatesRule/PresenterWithoutModule/Fixtures/templates/Forms/default.latte
@@ -58,6 +58,7 @@
 {form containerForm}
     {$form[part1][text1]->getHtmlId()}
     {input part1-text1}
+    {input part1-text2}
     {input part1-submit1}
 
     {input part2-text2}
diff --git a/tests/Rule/LatteTemplatesRule/PresenterWithoutModule/LatteTemplatesRuleForPresenterTest.php b/tests/Rule/LatteTemplatesRule/PresenterWithoutModule/LatteTemplatesRuleForPresenterTest.php
index e00f562a..0564c2bf 100644
--- a/tests/Rule/LatteTemplatesRule/PresenterWithoutModule/LatteTemplatesRuleForPresenterTest.php
+++ b/tests/Rule/LatteTemplatesRule/PresenterWithoutModule/LatteTemplatesRuleForPresenterTest.php
@@ -444,14 +444,29 @@ public function testForms(): void
                 48,
                 'default.latte',
             ],
+            [
+                'Form control with name "part1-text2" probably does not exist.',
+                61,
+                'default.latte',
+            ],
+            [
+                'Form control with name "5" probably does not exist.',
+                87,
+                'default.latte',
+            ],
             [
                 'Form control with name "5" probably does not exist.',
-                90,
+                91,
+                'default.latte',
+            ],
+            [
+                'Form control with name "1" probably does not exist.',
+                105,
                 'default.latte',
             ],
             [
                 'Form control with name "1" probably does not exist.',
-                108,
+                109,
                 'default.latte',
             ],
         ]);