Action! - Programming language

Action! is a programming language created in 1983.

#1176on PLDB

41Years Old

Action! is a procedural programming language similar to ALGOL 68 that is intended to produce high-performance programs for the Atari 8-bit family. The language was written by Clinton Parker and distributed on ROM cartridge by Optimized Systems Software starting in 1983. Action! was used to develop at least two commercial products—the Homepak productivity suite and Games Computers Play client program—and numerous programs in ANALOG Computing and Antic magazines. Read more on Wikipedia...

Tags: programming language
Early development of Action! happened in Optimized Systems Software
See also: (3 related languages) Optimized Systems Software, ALGOL 68, Atari BASIC

Example from Wikipedia:

BYTE RTCLOK=20, ; addr of sys timer
     SDMCTL=559 ; DMA control

BYTE ARRAY FLAGS(8190)

CARD COUNT,I,K,PRIME,TIME

PROC SIEVE()

  SDMCTL=0 ; shut off Antic
  RTCLOK=0 ; only one timer needed

  COUNT=0         ; init count
  FOR I=0 TO 8190 ; and flags
    DO
    FLAGS(I)='T ; "'T" is a compiler-provided constant for True
    OD

  FOR I=0 TO 8190 ; and flags
    DO
    IF FLAGS(I)='T THEN
      PRIME=I+I+3
      K=I+PRIME
      WHILE K<=8190
        DO
        FLAGS(K)='F ; "'F" is a compiler-provided constant for False
        K==+PRIME
        OD
      COUNT==+1
    FI
    OD
  TIME=RTCLOK ; get timer reading
  SDMCTL=34   ; restore screen

  PRINTF("%E %U PRIMES IN",COUNT)
  PRINTF("%E %U JIFFIES",TIME)
RETURN

Language features

Feature	Supported	Example	Token
Booleans	✓		True False
Print() Debugging	✓		PRINTF
Comments	✓	; A comment
Line Comments	✓	; A comment	;
Constructors	✓
Semantic Indentation	X