KISS OR      KISS XOR    KISS WITHIN

: >UP (( ch1 -- ch2 )
  XOR ( DUP
        WITHIN ( [CHAR] a [CHAR] z + 1 )
        AND BL
      ) ;
KISS >UP

EMIT ( >UP ( CHAR a ) )  \ A
CHAR A . SPACE           \  65
CHAR B 4 . SPACES        \     66
CHAR C . ( 10 SPACES )   \           67

Clear as mud?

The conclusion is unavoidable: KISS-commands in Forth are useful only to people that know their way with infix, prefix and postfix, and who can keep their bearings even when these notations are arbitrarily mixed.

To Forth it is no problem at all, it'll bring even the last four puzzles

. ( EMIT 107 3 + 4 )                      \ k7
. ( 7 . ( 8 * 2 ) + 8 )                   \ 16 15
. ( . 1 . ( 4 . 2 . 3 ) 6 . 5 )           \ 1 2 3 4 5 6
. ( ( 8 * 27 . DUP ) / ( 27 + 9 . DUP ) ) \ 216 36 6

to a good

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