GitHub - nikic/PHP-Parser: A PHP parser written in PHP
source link: https://github.com/nikic/PHP-Parser
Go to the source link to view the article. You can view the picture content, updated content and better typesetting reading experience. If the link is broken, please click the button below to view the snapshot at that time.
PHP Parser
This is a PHP 5.2 to PHP 8.2 parser written in PHP. Its purpose is to simplify static code analysis and manipulation.
Documentation for version 4.x (stable; for running on PHP >= 7.0; for parsing PHP 5.2 to PHP 8.2).
Documentation for version 3.x (unsupported; for running on PHP >= 5.5; for parsing PHP 5.2 to PHP 7.2).
Features
The main features provided by this library are:
- Parsing PHP 5, PHP 7, and PHP 8 code into an abstract syntax tree (AST).
- Invalid code can be parsed into a partial AST.
- The AST contains accurate location information.
- Dumping the AST in human-readable form.
- Converting an AST back to PHP code.
- Experimental: Formatting can be preserved for partially changed ASTs.
- Infrastructure to traverse and modify ASTs.
- Resolution of namespaced names.
- Evaluation of constant expressions.
- Builders to simplify AST construction for code generation.
- Converting an AST into JSON and back.
Quick Start
Install the library using composer:
php composer.phar require nikic/php-parser
Parse some PHP code into an AST and dump the result in human-readable form:
<?php
use PhpParser\Error;
use PhpParser\NodeDumper;
use PhpParser\ParserFactory;
$code = <<<'CODE'
<?php
function test($foo)
{
var_dump($foo);
}
CODE;
$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
try {
$ast = $parser->parse($code);
} catch (Error $error) {
echo "Parse error: {$error->getMessage()}\n";
return;
}
$dumper = new NodeDumper;
echo $dumper->dump($ast) . "\n";
This dumps an AST looking something like this:
array(
0: Stmt_Function(
byRef: false
name: Identifier(
name: test
)
params: array(
0: Param(
type: null
byRef: false
variadic: false
var: Expr_Variable(
name: foo
)
default: null
)
)
returnType: null
stmts: array(
0: Stmt_Expression(
expr: Expr_FuncCall(
name: Name(
parts: array(
0: var_dump
)
)
args: array(
0: Arg(
value: Expr_Variable(
name: foo
)
byRef: false
unpack: false
)
)
)
)
)
)
)
Let's traverse the AST and perform some kind of modification. For example, drop all function bodies:
use PhpParser\Node;
use PhpParser\Node\Stmt\Function_;
use PhpParser\NodeTraverser;
use PhpParser\NodeVisitorAbstract;
$traverser = new NodeTraverser();
$traverser->addVisitor(new class extends NodeVisitorAbstract {
public function enterNode(Node $node) {
if ($node instanceof Function_) {
// Clean out the function body
$node->stmts = [];
}
}
});
$ast = $traverser->traverse($ast);
echo $dumper->dump($ast) . "\n";
This gives us an AST where the Function_::$stmts
are empty:
array(
0: Stmt_Function(
byRef: false
name: Identifier(
name: test
)
params: array(
0: Param(
type: null
byRef: false
variadic: false
var: Expr_Variable(
name: foo
)
default: null
)
)
returnType: null
stmts: array(
)
)
)
Finally, we can convert the new AST back to PHP code:
use PhpParser\PrettyPrinter;
$prettyPrinter = new PrettyPrinter\Standard;
echo $prettyPrinter->prettyPrintFile($ast);
This gives us our original code, minus the var_dump()
call inside the function:
<?php
function test($foo)
{
}
For a more comprehensive introduction, see the documentation.
Documentation
Component documentation:
- Walking the AST
- Node visitors
- Modifying the AST from a visitor
- Short-circuiting traversals
- Interleaved visitors
- Simple node finding API
- Parent and sibling references
- Name resolution
- Name resolver options
- Name resolution context
- Pretty printing
- Converting AST back to PHP code
- Customizing formatting
- Formatting-preserving code transformations
- AST builders
- Fluent builders for AST nodes
- Lexer
- Lexer options
- Token and file positions for nodes
- Custom attributes
- Error handling
- Column information for errors
- Error recovery (parsing of syntactically incorrect code)
- Constant expression evaluation
- Evaluating constant/property/etc initializers
- Handling errors and unsupported expressions
- JSON representation
- JSON encoding and decoding of ASTs
- Performance
- Disabling Xdebug
- Reusing objects
- Garbage collection impact
- Frequently asked questions
- Parent and sibling references
Recommend
-
253
Diablo II character file parser D2s is a binary parser written in Go that's used to parse .d2s files. This is the binary format that the game Diablo II uses...
-
99
php-parser - A Parser for PHP written in Go
-
76
PHP-Parser - A PHP parser written in PHP
-
72
PHP Parser written in Go This project uses goyacc
-
33
Name: language_evolution Date: 2020-02-18 Author: Nikita Popov [email protected] Proposed Version: PHP 8.0 RFC PR:
-
15
Like crater, but for PHP. Contribute to nikic/php-crater development by creating an account on GitHub.
-
3
Copy link Contributor Author nikic ...
-
4
New issue Backport some LLVM compile-time improvements #82783 Convers...
-
11
Copy link Contributor nikic commented...
-
10
Copy link Contributor nikic
About Joyk
Aggregate valuable and interesting links.
Joyk means Joy of geeK