unquote-splicing

[auxiliary syntax] unquote datum

[auxiliary syntax] unquote-splicing datum

R5RS: When appears in quasiquote template, evaluates and inserts the value of datum.

[auxiliary syntax] unquote datum ...

[auxiliary syntax] unquote-splicing datum ...

R6RS: Allows zero or more datums if the unquote or unquote-splicing form is at the splicing position of a quasiquote template.

See also quasiquote, ,, ,@.