(BLISS, or allegedly, "System Software
Implementation Language, Backwards") A language designed by
W.A. Wulf at
CMU around 1969.
BLISS is an expression language. It is
block-structured,
and typeless, with
exception handling facilities,
coroutines, a
macro system, and a highly
optimising compiler. It was one of the first non-assembly languages
for
operating system implementation. It gained fame for its
lack of a
goto and also lacks implicit dereferencing: all
symbols stand for addresses, not values.
Another characteristic (and possible explanation for the
backward acronym) was that BLISS fairly uniformly used
backward keywords for closing blocks, a famous example being
ELUDOM to close a MODULE. An exception was BEGIN...END though
you could use (...) instead.
DEC introduced the NOVALUE keyword in their dialects to allow
statements to not return a value.
Versions: CMU
BLISS-10 for the PDP-10; CMU
BLISS-11,
BLISS-16, DEC
BLISS-16C, DEC
BLISS-32,
BLISS-36 for
VAX/
VMS, BLISS-36C.
["BLISS: A Language for Systems Programming", CACM
14(12):780-790, Dec 1971].