What's wrong with your HEAD?

[Werner]

That's why, in my GX library for the SX, I implemented HEAD as

Code:

ASSEMBLE
        CON(1)  8
RPL
xNAME HEAD
::
  CK1&Dispatch
  FIVE
  ::
    >R
    ticR
    ITE
    RDROP
    INVDIMERR
  ;
  THREE
  ::
    DUPLEN$ #0=case INVDIMERR
    CAR$
    CHR>$
  ;
;

Where INVDIMERR is

Code:

NULLNAME INVDIMERR
:: # 501 ERROROUT ;

Cheers, Werner