S.I/Lisp/

APPEND

=APPEND(A1:A5, A6:A10)
-> A1:A10

=APPEND(A1:E1, F1:J1)
-> A1:J1
        

DEFINE(
    APPEND,
    LAMBDA(
        head,
        body,
        IF(
            GREATERTHAN(
                COLUMNS(body),
                ROWS(body)),
            HSTACK(
                head,
                body),
            VSTACK(
                head,
                body))))
        

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