S.I/Lisp/

ALPHABET

=ALPHABET()
-> {"A","B","C", ...}

=ALPHABET(YES)
-> {"A";"B";"C"; ...}
        

DEFINE(
    ALPHABET,
    LAMBDA(
        [vertical],
        LET(
            alphabet,
                HSTACK(
                    {"A","B","C","D","E","F"},
                    {"G","H","I","J","K","L"},
                    {"M","N","O","P","Q","R"},
                    {"S","T","U","V","W","X","Y","Z"}),
            IF(
                DEFAULT(vertical, NO),
                TRANSPOSE(alphabet),
                alphabet))))
        

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