Type Parser Component

The parser component analyzes a TypeLang type declaration string and builds an AST (Abstract Syntax Tree) out of it, checking the grammar along the way.

Installation

Requirements:

PHP >= 8.4

Quick Start

The TypeLang\Parser\TypeParser class is the entry point of the component. Its parse() method turns a type declaration string into a TypeLang\Type\TypeNode instance.

$parser = new TypeLang\Parser\TypeParser();

$type = $parser->parse('array{ key: int }');

var_dump($type);

object(TypeLang\Type\NamedTypeNode)#1 (4) { ["offset"]=> int(0) ["name"]=> object(TypeLang\Type\Name)#2 (3) { ["offset"]=> int(0) ["segments"]=> array(1) { [0]=> object(TypeLang\Type\Identifier)#3 (2) { ["offset"]=> int(0) ["value"]=> string(5) "array" } } ["isFullyQualified"]=> bool(false) } ["arguments"]=> NULL ["fields"]=> object(TypeLang\Type\Shape\FieldsListNode)#4 (3) { ["offset"]=> int(7) ["items"]=> array(1) { [0]=> object(TypeLang\Type\Shape\NamedFieldNode)#5 (5) { ... } } ["sealed"]=> bool(true) } }

Every node exposes an $offset (byte offset in the source where the node starts) and, depending on its kind, a handful of other public properties. The node classes themselves (TypeLang\Type\*) belong to the separate type-lang/types package — plain AST Nodes.

Strict vs. Tolerant Parsing

TypeParser implements two parsing strategies, both declared on TypeParserInterface:

parse(): TypeNode — strict mode. Requires the whole input to be a syntactically valid type statement; throws a ParserExceptionInterface on the first error.
parseTolerant(): ParsedResult — tolerant mode. Parses as much of the input as it can and returns a TypeLang\Parser\ParsedResult object containing the (possibly partial) type and the offset up to which the source was actually consumed — regardless of what follows. Useful for phpdoc/docblock parsing where a type declaration is followed by a free-text description. See Tolerant mode.

Parser Arguments

The parse()/parseTolerant() methods accept the source code in any of the following forms:

$type = $parser->parse(<<<'CODE'
    object{ key?: int<0, max> }
CODE);

$type = $parser->parse(
    fopen(__DIR__ . '/source.txt', 'rb'),
);

$type = $parser->parse(
    new SplFileInfo(__DIR__ . '/source.txt'),
);

$type = $parser->parse(
    Phplrt\Source\File::fromPathname(__DIR__ . '/source.txt'),
);

What's Next

Feature toggling: Enable or disable individual language constructs (generics, shapes, unions, ...) — see Feature Toggling.
Tolerant mode: Parse a type declaration embedded in free-form text, such as a phpdoc annotation — see Tolerant Mode.
Visitors: Traverse, search, and rewrite a parsed AST — see Visitors.
Name resolution: Resolve short/relative names in an AST against use statements or any other custom rule — see Name Resolution.

05 July 2026