typedduck/steins-attributes

Effect-envelope attributes for the PHP;STEINS static analyzer: #[Pure] and #[Effect]. Inert at runtime.

v0.1.0 2026-07-25 09:51 UTC

Requires

• php: >=8.1

MIT

• USAMI Kenta

• attributes
• static analysis
• effects
• purity

Published on Packagist.org on 2026-07-25 09:58 UTC

README

Effect-envelope attributes for PHP;STEINS, a value-precise static analyzer for PHP. Two classes, both inert at runtime.

composer require --dev typedduck/steins-attributes

use Steins\Effect;
use Steins\Pure;

#[Pure]
function slugify(string $title): string
{
    return strtolower(trim($title));
}

#[Effect('io.fs.write', 'nondet.time')]
function appendAudit(string $line): void
{
    file_put_contents('/var/log/audit', date('c') . " {$line}\n", FILE_APPEND);
}

An envelope is an upper bound you assert, and Steins reports what it does not admit. Checking is by prefix, so a declared io admits an inferred io.net.http. #[Pure] is the empty envelope.

Labels must be plain string literals. A class constant, a concatenation, or a named argument makes the whole attribute unrecognized — no envelope, no checking, silently. Which is why there is no constants class for them.

Known labels: output, output.header; io, io.fs, io.fs.read, io.fs.write, io.net, io.net.http, io.db, io.ipc, io.process, io.signal; global.read, global.write; nondet, nondet.random, nondet.time; mutate, exit, ffi; failure, failure.environment, failure.input, failure.resource. Anything else is effect.unknown-label.

Write them fully qualified, qualified, or bare under a use import (use Steins\Pure as P; makes #[P] work). A bare #[Pure] without the import is not recognized — JetBrains' #[Pure] is a different attribute.

--dev is right, and as a fact rather than a convention: code declaring these runs with the classes absent entirely, and only newInstance() needs them — which only a development tool calls. Installing them alone is a fine end state if you do not want the analyzer; installing the analyzer brings them along.

Copyright

This package is licensed under MIT License.

Copyright (c) 2026 TypedDuck, USAMI Kenta <[e-mail]>

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.