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filter is not described

wp_sprintf filter-hook . WP 2.5.0

Filters a fragment from the pattern passed to wp_sprintf().

If the fragment is unchanged, then sprintf() will be run on the fragment.

Usage

add_filter( 'wp_sprintf', 'filter_function_name_6627', 10, 2 );
function filter_function_name_6627( $fragment, $arg ){
	// filter...

	return $fragment;
}
$fragment(string)
A fragment from the pattern.
$arg(string)
The argument.

Where the hook is called

wp_sprintf()
wp_sprintf
wp-includes/formatting.php 4456
$_fragment = apply_filters( 'wp_sprintf', $fragment, $arg );

Where the hook is used (in WP core)

wp-includes/default-filters.php 189
add_filter( 'wp_sprintf', 'wp_sprintf_l', 10, 2 );