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    <h3>Editing: LinesOfCode.php</h3>
    <textarea name="content" rows="20" cols="80">&lt;?php declare(strict_types=1);
/*
 * This file is part of sebastian/lines-of-code.
 *
 * (c) Sebastian Bergmann &lt;sebastian@phpunit.de&gt;
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */
namespace SebastianBergmann\LinesOfCode;

/**
 * @psalm-immutable
 */
final class LinesOfCode
{
    /**
     * @var int
     */
    private $linesOfCode;

    /**
     * @var int
     */
    private $commentLinesOfCode;

    /**
     * @var int
     */
    private $nonCommentLinesOfCode;

    /**
     * @var int
     */
    private $logicalLinesOfCode;

    /**
     * @throws IllogicalValuesException
     * @throws NegativeValueException
     */
    public function __construct(int $linesOfCode, int $commentLinesOfCode, int $nonCommentLinesOfCode, int $logicalLinesOfCode)
    {
        if ($linesOfCode &lt; 0) {
            throw new NegativeValueException('$linesOfCode must not be negative');
        }

        if ($commentLinesOfCode &lt; 0) {
            throw new NegativeValueException('$commentLinesOfCode must not be negative');
        }

        if ($nonCommentLinesOfCode &lt; 0) {
            throw new NegativeValueException('$nonCommentLinesOfCode must not be negative');
        }

        if ($logicalLinesOfCode &lt; 0) {
            throw new NegativeValueException('$logicalLinesOfCode must not be negative');
        }

        if ($linesOfCode - $commentLinesOfCode !== $nonCommentLinesOfCode) {
            throw new IllogicalValuesException('$linesOfCode !== $commentLinesOfCode + $nonCommentLinesOfCode');
        }

        $this-&gt;linesOfCode           = $linesOfCode;
        $this-&gt;commentLinesOfCode    = $commentLinesOfCode;
        $this-&gt;nonCommentLinesOfCode = $nonCommentLinesOfCode;
        $this-&gt;logicalLinesOfCode    = $logicalLinesOfCode;
    }

    public function linesOfCode(): int
    {
        return $this-&gt;linesOfCode;
    }

    public function commentLinesOfCode(): int
    {
        return $this-&gt;commentLinesOfCode;
    }

    public function nonCommentLinesOfCode(): int
    {
        return $this-&gt;nonCommentLinesOfCode;
    }

    public function logicalLinesOfCode(): int
    {
        return $this-&gt;logicalLinesOfCode;
    }

    public function plus(self $other): self
    {
        return new self(
            $this-&gt;linesOfCode() + $other-&gt;linesOfCode(),
            $this-&gt;commentLinesOfCode() + $other-&gt;commentLinesOfCode(),
            $this-&gt;nonCommentLinesOfCode() + $other-&gt;nonCommentLinesOfCode(),
            $this-&gt;logicalLinesOfCode() + $other-&gt;logicalLinesOfCode(),
        );
    }
}
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