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filter is not described

comment_excerpt_length filter-hook . WP 4.4.0

Filters the amount of words used in the comment excerpt.

Usage

add_filter( 'comment_excerpt_length', 'filter_function_name_9073' );
function filter_function_name_9073( $comment_excerpt_length ){
	// filter...

	return $comment_excerpt_length;
}
$comment_excerpt_length(int)
The amount of words you want to display in the comment excerpt.

Where the hook is called

get_comment_excerpt()
comment_excerpt_length
wp-includes/comment-template.php 597
$comment_excerpt_length = apply_filters( 'comment_excerpt_length', 20 );

Where the hook is used (in WP core)

Does not used.