Text

Use original line numbers for a fixed range, or literal source text for known boundaries. Prefer a structural selector when a supported declaration has a stable name. HTML, SVG, YAML, Markdown, and environment files can all be sliced this way; no comment markers need to be added.

All four search case-sensitive substrings inside the current slice. They do not match nested HTML elements, YAML mappings, or Markdown sections structurally. Use method(), rule(), or block() when the source language provides them.

The PHP selections below assume installation is complete and Composer's autoloader is loaded. Save each input under the filename shown before running its PHP selection. Choose these selectors when you know the exact text or original line numbers.

Select exact source lines

This standalone example selects one original source line without relying on language detection:

<?php

require __DIR__.'/vendor/autoload.php';

use Alto\Code\Slicer\CodeSource;

$source = CodeSource::fromString("first\nsecond\nthird");
echo $source->lines(2, 2)->content(), "\n";

Save it beside vendor, then run it with PHP. It prints:

second

Use after() and before() for boundaries within a line; use the line helpers below when the matching lines themselves should be included or excluded.

HTML: include a complete form

Source: checkout.html

<main>
    <form action="/orders" method="post">
        <input name="email" type="email" required>
        <button type="submit">Confirm</button>
    </form>
    <p>Payment is collected on confirmation.</p>
</main>

Selection

<?php

use Alto\Code\Slicer\CodeSource;

$slice = CodeSource::fromFile('checkout.html')->slice()
    ->fromLine('<form ')
    ->throughLine('</form>');
echo $slice->content();

Result

    <form action="/orders" method="post">
        <input name="email" type="email" required>
        <button type="submit">Confirm</button>
    </form>

To keep only its contents, exclude the matching tag lines:

Selection

<?php

use Alto\Code\Slicer\CodeSource;

$slice = CodeSource::fromFile('checkout.html')->slice()
    ->afterLine('<form ')
    ->beforeLine('</form>');
echo $slice->content();

Result

        <input name="email" type="email" required>
        <button type="submit">Confirm</button>

SVG: select a group

Source: confirmed.svg

<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24">
    <title>Order confirmed</title>
    <g id="badge" fill="none" stroke="currentColor">
        <circle cx="12" cy="12" r="10"/>
        <path d="m7 12 3 3 7-7"/>
    </g>
</svg>

Selection

<?php

use Alto\Code\Slicer\CodeSource;

$slice = CodeSource::fromFile('confirmed.svg')->slice()
    ->fromLine('<g id="badge"')
    ->throughLine('</g>');
echo $slice->content();

Result

    <g id="badge" fill="none" stroke="currentColor">
        <circle cx="12" cy="12" r="10"/>
        <path d="m7 12 3 3 7-7"/>
    </g>

This group has no nested g. With nested groups, throughLine('</g>') would stop at the first closing line, so it cannot stand in for an element selector.

YAML: select known settings

Source: checkout.yaml

app:
  name: Checkout
  currency: EUR
services:
  App\Checkout:
    arguments:
      $taxRate: 1.2
      $currency: '%app.currency%'
receipt:
  subject: Your order is confirmed

Selection

<?php

use Alto\Code\Slicer\CodeSource;

$slice = CodeSource::fromFile('checkout.yaml')->slice()
    ->fromLine('services:')
    ->beforeLine('receipt:');
echo $slice->content();

Result

services:
  App\Checkout:
    arguments:
      $taxRate: 1.2
      $currency: '%app.currency%'

The keys are text boundaries. This selection does not infer YAML indentation or resolve a key path.

Markdown: select a section between headings

Source: checkout.md

# Checkout

## Installation

Install the package with Composer.

## Usage

Load your source and select a method.

Selection

<?php

use Alto\Code\Slicer\CodeSource;

$slice = CodeSource::fromFile('checkout.md')->slice()
    ->fromLine('## Installation')
    ->beforeLine('## Usage');
echo $slice->content();

Result

## Installation

Install the package with Composer.

The blank line before the next heading is preserved. Both heading texts are supplied explicitly.

Environment files: select variable assignments

Source: .env.example

APP_ENV=dev
APP_NAME="Checkout demo"
APP_URL=http://localhost:8000
ASSET_URL=${APP_URL}/assets
MAILER_DSN=null://null

Selection

<?php

use Alto\Code\Slicer\CodeSource;

$slice = CodeSource::fromFile('.env.example', 'dotenv')->slice()
    ->fromLine('APP_NAME=')
    ->throughLine('ASSET_URL=');
echo $slice->content();

Result

APP_NAME="Checkout demo"
APP_URL=http://localhost:8000
ASSET_URL=${APP_URL}/assets

The source is read as text. Environment variables are not loaded or expanded.

Exact lines and text within a line

lines(4, 8) selects inclusive line numbers from the original file. after('return ') and before(';') cut at exact text inside a line and exclude that text. These methods also work when the source language is unknown.

Every selection retains the original bytes and source line numbers. Empty or multiline search text is rejected by the line helpers; missing text throws SourceTextNotFound.

See the public API or return to the language guides.