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filter is not described

pre_category_nicename filter-hook . WP 2.0.3

Filters the category nicename before it is sanitized.

Use the {@see 'pre_$taxonomy_$field'} hook instead.

Usage

add_filter( 'pre_category_nicename', 'filter_function_name_5895' );
function filter_function_name_5895( $value ){
	// filter...

	return $value;
}
$value(string)
The category nicename.

Where the hook is called

sanitize_term_field()
wp-includes/taxonomy.php 1516
$value = apply_filters( 'pre_category_nicename', $value );

Where the hook is used (in WP core)

Does not used.