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PHP Parser |
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========== |
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|
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[](https://coveralls.io/github/nikic/PHP-Parser?branch=master](https://coveralls.io/github/nikic/PHP-Parser?branch=master](https://coveralls.io/github/nikic/PHP-Parser?branch=master) |
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|
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This is a PHP parser written in PHP. Its purpose is to simplify static code analysis and |
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manipulation. |
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|
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[**Documentation for version 5.x**][doc_master] (current; for running on PHP >= 7.4; for parsing PHP 7.0 to PHP 8.3, with limited support for parsing PHP 5.x). |
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|
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[Documentation for version 4.x][doc_4_x] (supported; for running on PHP >= 7.0; for parsing PHP 5.2 to PHP 8.3). |
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|
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Features |
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-------- |
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|
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The main features provided by this library are: |
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|
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* Parsing PHP 7, and PHP 8 code into an abstract syntax tree (AST). |
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* Invalid code can be parsed into a partial AST. |
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* The AST contains accurate location information. |
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* Dumping the AST in human-readable form. |
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* Converting an AST back to PHP code. |
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* Formatting can be preserved for partially changed ASTs. |
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* Infrastructure to traverse and modify ASTs. |
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* Resolution of namespaced names. |
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* Evaluation of constant expressions. |
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* Builders to simplify AST construction for code generation. |
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* Converting an AST into JSON and back. |
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|
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Quick Start |
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----------- |
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|
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Install the library using [](https://getcomposer.orgcomposer](https://getcomposer.org](https://getcomposer.org): |
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|
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php composer.phar require nikic/php-parser |
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|
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Parse some PHP code into an AST and dump the result in human-readable form: |
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|
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```php |
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<?php |
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use PhpParser\Error; |
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use PhpParser\NodeDumper; |
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use PhpParser\ParserFactory; |
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|
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$code = <<<'CODE' |
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<?php |
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|
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function test($foo) |
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{ |
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var_dump($foo); |
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} |
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CODE; |
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|
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$parser = (new ParserFactory())->createForNewestSupportedVersion(); |
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try { |
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$ast = $parser->parse($code); |
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} catch (Error $error) { |
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echo "Parse error: {$error->getMessage()}\n"; |
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return; |
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} |
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|
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$dumper = new NodeDumper; |
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echo $dumper->dump($ast) . "\n"; |
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``` |
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|
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This dumps an AST looking something like this: |
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|
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``` |
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array( |
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0: Stmt_Function( |
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attrGroups: array( |
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) |
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byRef: false |
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name: Identifier( |
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name: test |
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) |
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params: array( |
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0: Param( |
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attrGroups: array( |
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) |
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flags: 0 |
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type: null |
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byRef: false |
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variadic: false |
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var: Expr_Variable( |
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name: foo |
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) |
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default: null |
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) |
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) |
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returnType: null |
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stmts: array( |
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0: Stmt_Expression( |
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expr: Expr_FuncCall( |
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name: Name( |
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name: var_dump |
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) |
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args: array( |
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0: Arg( |
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name: null |
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value: Expr_Variable( |
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name: foo |
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) |
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byRef: false |
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unpack: false |
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) |
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) |
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) |
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) |
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) |
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) |
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) |
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``` |
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|
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Let's traverse the AST and perform some kind of modification. For example, drop all function bodies: |
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|
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```php |
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use PhpParser\Node; |
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use PhpParser\Node\Stmt\Function_; |
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use PhpParser\NodeTraverser; |
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use PhpParser\NodeVisitorAbstract; |
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|
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$traverser = new NodeTraverser(); |
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$traverser->addVisitor(new class extends NodeVisitorAbstract { |
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public function enterNode(Node $node) { |
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if ($node instanceof Function_) { |
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// Clean out the function body |
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$node->stmts = []; |
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} |
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} |
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}); |
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|
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$ast = $traverser->traverse($ast); |
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echo $dumper->dump($ast) . "\n"; |
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``` |
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|
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This gives us an AST where the `Function_::$stmts` are empty: |
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|
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``` |
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array( |
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0: Stmt_Function( |
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attrGroups: array( |
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) |
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byRef: false |
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name: Identifier( |
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name: test |
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) |
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params: array( |
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0: Param( |
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attrGroups: array( |
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) |
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type: null |
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byRef: false |
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variadic: false |
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var: Expr_Variable( |
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name: foo |
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) |
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default: null |
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) |
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) |
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returnType: null |
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stmts: array( |
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) |
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) |
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) |
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``` |
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|
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Finally, we can convert the new AST back to PHP code: |
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|
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```php |
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use PhpParser\PrettyPrinter; |
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|
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$prettyPrinter = new PrettyPrinter\Standard; |
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echo $prettyPrinter->prettyPrintFile($ast); |
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``` |
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|
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This gives us our original code, minus the `var_dump()` call inside the function: |
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|
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```php |
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<?php |
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|
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function test($foo) |
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{ |
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} |
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``` |
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|
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For a more comprehensive introduction, see the documentation. |
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|
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Documentation |
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------------- |
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|
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1. [](doc/0_Introduction.markdownIntroduction](doc/0_Introduction.markdown](doc/0_Introduction.markdown) |
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2. [](doc/2_Usage_of_basic_components.markdownUsage of basic components](doc/2_Usage_of_basic_components.markdown](doc/2_Usage_of_basic_components.markdown) |
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|
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Component documentation: |
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|
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* [](doc/component/Walking_the_AST.markdownWalking the AST](doc/component/Walking_the_AST.markdown](doc/component/Walking_the_AST.markdown) |
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* Node visitors |
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* Modifying the AST from a visitor |
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* Short-circuiting traversals |
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* Interleaved visitors |
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* Simple node finding API |
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* Parent and sibling references |
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* [](doc/component/Name_resolution.markdownName resolution](doc/component/Name_resolution.markdown](doc/component/Name_resolution.markdown) |
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* Name resolver options |
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* Name resolution context |
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* [](doc/component/Pretty_printing.markdownPretty printing](doc/component/Pretty_printing.markdown](doc/component/Pretty_printing.markdown) |
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* Converting AST back to PHP code |
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* Customizing formatting |
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* Formatting-preserving code transformations |
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* [](doc/component/AST_builders.markdownAST builders](doc/component/AST_builders.markdown](doc/component/AST_builders.markdown) |
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* Fluent builders for AST nodes |
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* [](doc/component/Lexer.markdownLexer](doc/component/Lexer.markdown](doc/component/Lexer.markdown) |
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* Emulation |
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* Tokens, positions and attributes |
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* [](doc/component/Error_handling.markdownError handling](doc/component/Error_handling.markdown](doc/component/Error_handling.markdown) |
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* Column information for errors |
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* Error recovery (parsing of syntactically incorrect code) |
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* [](doc/component/Constant_expression_evaluation.markdownConstant expression evaluation](doc/component/Constant_expression_evaluation.markdown](doc/component/Constant_expression_evaluation.markdown) |
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* Evaluating constant/property/etc initializers |
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* Handling errors and unsupported expressions |
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* [](doc/component/JSON_representation.markdownJSON representation](doc/component/JSON_representation.markdown](doc/component/JSON_representation.markdown) |
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* JSON encoding and decoding of ASTs |
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* [](doc/component/Performance.markdownPerformance](doc/component/Performance.markdown](doc/component/Performance.markdown) |
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* Disabling Xdebug |
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* Reusing objects |
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* Garbage collection impact |
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* [](doc/component/FAQ.markdownFrequently asked questions](doc/component/FAQ.markdown](doc/component/FAQ.markdown) |
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* Parent and sibling references |
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|
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[doc_3_x]: https://github.com/nikic/PHP-Parser/tree/3.x/doc |
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[doc_4_x]: https://github.com/nikic/PHP-Parser/tree/4.x/doc |
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[doc_master]: https://github.com/nikic/PHP-Parser/tree/master/doc |
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|
