<form method="POST">
    <h3>Editing: ManagesStacks.php</h3>
    <textarea name="content" rows="20" cols="80">&lt;?php

namespace Illuminate\View\Concerns;

use InvalidArgumentException;

trait ManagesStacks
{
    /**
     * All of the finished, captured push sections.
     *
     * @var array
     */
    protected $pushes = [];

    /**
     * All of the finished, captured prepend sections.
     *
     * @var array
     */
    protected $prepends = [];

    /**
     * The stack of in-progress push sections.
     *
     * @var array
     */
    protected $pushStack = [];

    /**
     * Start injecting content into a push section.
     *
     * @param  string  $section
     * @param  string  $content
     * @return void
     */
    public function startPush($section, $content = '')
    {
        if ($content === '') {
            if (ob_start()) {
                $this-&gt;pushStack[] = $section;
            }
        } else {
            $this-&gt;extendPush($section, $content);
        }
    }

    /**
     * Stop injecting content into a push section.
     *
     * @return string
     *
     * @throws \InvalidArgumentException
     */
    public function stopPush()
    {
        if (empty($this-&gt;pushStack)) {
            throw new InvalidArgumentException('Cannot end a push stack without first starting one.');
        }

        return tap(array_pop($this-&gt;pushStack), function ($last) {
            $this-&gt;extendPush($last, ob_get_clean());
        });
    }

    /**
     * Append content to a given push section.
     *
     * @param  string  $section
     * @param  string  $content
     * @return void
     */
    protected function extendPush($section, $content)
    {
        if (! isset($this-&gt;pushes[$section])) {
            $this-&gt;pushes[$section] = [];
        }

        if (! isset($this-&gt;pushes[$section][$this-&gt;renderCount])) {
            $this-&gt;pushes[$section][$this-&gt;renderCount] = $content;
        } else {
            $this-&gt;pushes[$section][$this-&gt;renderCount] .= $content;
        }
    }

    /**
     * Start prepending content into a push section.
     *
     * @param  string  $section
     * @param  string  $content
     * @return void
     */
    public function startPrepend($section, $content = '')
    {
        if ($content === '') {
            if (ob_start()) {
                $this-&gt;pushStack[] = $section;
            }
        } else {
            $this-&gt;extendPrepend($section, $content);
        }
    }

    /**
     * Stop prepending content into a push section.
     *
     * @return string
     *
     * @throws \InvalidArgumentException
     */
    public function stopPrepend()
    {
        if (empty($this-&gt;pushStack)) {
            throw new InvalidArgumentException('Cannot end a prepend operation without first starting one.');
        }

        return tap(array_pop($this-&gt;pushStack), function ($last) {
            $this-&gt;extendPrepend($last, ob_get_clean());
        });
    }

    /**
     * Prepend content to a given stack.
     *
     * @param  string  $section
     * @param  string  $content
     * @return void
     */
    protected function extendPrepend($section, $content)
    {
        if (! isset($this-&gt;prepends[$section])) {
            $this-&gt;prepends[$section] = [];
        }

        if (! isset($this-&gt;prepends[$section][$this-&gt;renderCount])) {
            $this-&gt;prepends[$section][$this-&gt;renderCount] = $content;
        } else {
            $this-&gt;prepends[$section][$this-&gt;renderCount] = $content.$this-&gt;prepends[$section][$this-&gt;renderCount];
        }
    }

    /**
     * Get the string contents of a push section.
     *
     * @param  string  $section
     * @param  string  $default
     * @return string
     */
    public function yieldPushContent($section, $default = '')
    {
        if (! isset($this-&gt;pushes[$section]) &amp;&amp; ! isset($this-&gt;prepends[$section])) {
            return $default;
        }

        $output = '';

        if (isset($this-&gt;prepends[$section])) {
            $output .= implode(array_reverse($this-&gt;prepends[$section]));
        }

        if (isset($this-&gt;pushes[$section])) {
            $output .= implode($this-&gt;pushes[$section]);
        }

        return $output;
    }

    /**
     * Flush all of the stacks.
     *
     * @return void
     */
    public function flushStacks()
    {
        $this-&gt;pushes = [];
        $this-&gt;prepends = [];
        $this-&gt;pushStack = [];
    }
}
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