Altered version of docl's 'key' handler with commentary

gistfile1.txt

Original from docl:
: :: here ] ;
: nv-key ['] key 2 + compile ; immediate  ( unvectored key )
:: nv-key dup 27 =if nv-key dup . nip ;then ; is key


Rather than "nv-key", a more generic word to get the default (non-vectored) definition can be used:

: default: ' drop which @ d->xt @ 2 + compile ; immediate

This uses a couple of tricks:

  ' drop    :::   Find a word and discard the XT
  which @   :::   Get the dictionary header of the most recently found word
  d->xt @   :::   Get the XT from the dictionary header
  2 +       :::   Skip past the vector prefix to the default definition
  compile   :::   Compile a call to the default definition

OR:

: default ' 2 + compile ; immediate

  '         :::   Find a word and get the XT
  2 +       :::   Skip past the vector prefix to the default definition
  compile   :::   Compile a call to the default definition

With this, the the code becomes:

: :: here ] ;   
:: default: key dup 27 =if drop default: key dup . then ; is key

(Note slight restructuring to generate slightly more optimal code: only one return point, and 'drop' is faster than 'nip')

Overall, with stack comments:

: default:  ( "- ) ' drop which @ d->xt @ 2 + compile ; immediate
: ::        ( -a ) here ] ;   
::          ( -c ) default: key dup 27 =if drop default: key dup . then ; is key

gistfile2.txt

ok : :: here ] ; 
ok : nv-key ['] key 2 + compile ; 
ok immediate 
ok  ( unvectored key )
ok  :: nv-key dup 27 =if nv-key dup . nip ;then ; 
ok is key 
ok 119 w111 o114 r100 d115 s32  nv-key :: compile-only .compiler see show dump set-blocks e new i ia n p x d s v (ia) (e) (v) (line) (block) block blk line-ending offset #-block-size #-blocks does> find binary octal hex decimal reclass forget ." < > <> = ;then if FALSE TRUE ` immediate fill copy constant variable variable: allot }} ---reveal--- {{ } { <list> -- ++ >in base whitespace which heap #mem fh fw fb update tib compiler last ( next for ['] pop push 0; again repeat then !if <if >if =if ;; ; [ s" >tib isNumber? listen ok >number save notfound reset depth boot d->name d->xt d->class .data .macro .word with-class (remap-keys) bye getLength keepString redraw tempString literal, compile devector is :devector :is -! +! !+ @+ ' wait compare " . execute neg mod / off on 2dup tuck -rot rot not 2drop over key words clear type emit cr later : create ] , here accept out in dup nip >> << /mod * - + ! @ xor or and drop swap 1- 1+ 
ok