Writing Parsers in PHP

Learn how to write streaming generator parsers in PHP.

AMPHP is a collection of event-driven libraries for PHP designed with fibers and concurrency in mind. amphp/parser allows easily building streaming generator parsers.


This package can be installed as a Composer dependency.

composer require amphp/parser


  • PHP 7.4+


PHP’s generators are a great way for building incremental parsers.


This simple parser parses a line delimited protocol and prints a message for each line. Instead of printing a message, you could also invoke a data callback.

$parser = new Parser((function () {
    while (true) {
        $line = yield "\r\n";

        if (trim($line) === "") {

        print "New item: {$line}" . PHP_EOL;

for ($i = 0; $i < 100; $i++) {

Furthere examples can be found in other AMPHP packages which this library to build streaming parsers.

Yield Behavior

You can either yield a string that’s used as delimiter, an integer that’s used as length, or null to flush any remaining buffer in the parser (if any) or await the next call to Parser::push().


amphp/parser follows the semver semantic versioning specification like all other amphp packages.


If you discover any security related issues, please email [email protected] instead of using the issue tracker.


The MIT License (MIT). Please see LICENSE for more information.