CONCATENATE.html -- ACL2 Version 6.3

### CONCATENATE

concatenate lists or strings together

    Major Section:  ACL2-BUILT-INS

    Examples:
    (concatenate 'string "ab" "cd" "ef")     ; equals "abcdef"
    (concatenate 'string "ab")               ; equals "ab"
    (concatenate 'list '(a b) '(c d) '(e f)) ; equals '(a b c d e f)
    (concatenate 'list)                      ; equals nil

    General Form:
    (concatenate result-type x1 x2 ... xn)

where `n >= 0` and either: `result-type` is `'``string` and each `xi` is a string; or `result-type` is `'``list` and each `xi` is a true list. `Concatenate` simply concatenates its arguments to form the result string or list. Also see append and see string-append. (The latter immediately generates a call to `concatenate` when applied to strings.)

Note: We do *not* try to comply with the Lisp language's insistence that `concatenate` copies its arguments. Not only are we in an applicative setting, where this issue shouldn't matter for the logic, but also we do not actually modify the underlying lisp implementation of `concatenate`; we merely provide a definition for it.

`Concatenate` is a Common Lisp function. See any Common Lisp documentation for more information.