Execute shortcode only in another shortcode

Question

I wonder if it's possible to do a shortcode only in another shortcode. For example I got following code pieces:

[heading]some pricing page[/heading]
[pricing_box]
  [heading]Some title[/heading]
[/pricing_box]

Now I don't want to define one shortcode heading which would apply to both the nested one and the first level shortcode. I want the both heading shortcodes to produce different outputs. Of course, I could try to solve this by renaming one of the shortcodes to title or something, but this doesn't always result in optimal naming arrangements.

Answer 1

To use a different callback for the nested headings switch the shortcode handler in the pricing_box callback and restore the main handler before you return the string.

add_shortcode( 'pricing_box', 'shortcode_pricing_box' );
add_shortcode( 'heading',     'shortcode_heading_main' );

function shortcode_pricing_box( $atts, $content = '' )
{
    // switch shortcode handlers
    add_shortcode( 'heading', 'shortcode_heading_pricing_box' );

    $out = '<div class="pricing-box">' . do_shortcode( $content ) . '</div>';

    // restore main handler
    add_shortcode( 'heading', 'shortcode_heading_main' );

    return $out;
}

function shortcode_heading_main( $atts, $content = '' )
{
    return "<h2>$content</h2>";
}

function shortcode_heading_pricing_box( $atts, $content = '' )
{
    return "<h3>$content</h3>";
}