FLOW-MATIC


FLOW-MATIC, originally known as B-0, was the first English-like data processing language. It was developed for the UNIVAC I at Remington Rand under Grace Hopper from 1955 to 1959, and helped shape the development of COBOL.

Development

Hopper had found that business data processing customers were uncomfortable with mathematical notation:
In late 1953, she proposed that data processing problems should be expressed using English keywords, but Rand management considered the idea infeasible. In early 1955, she and her team wrote a specification for such a programming language and implemented a prototype. The FLOW-MATIC compiler became publicly available in early 1958 and was substantially complete in 1959.

Innovations and influence

FLOW-MATIC was the first programming language to express operations using English-like statements. It was also the first system to distinctly separate the description of data from the operations on it. Its data definition language, unlike its executable statements, was not English-like; rather, data structures were defined by filling in pre-printed forms.
FLOW-MATIC and its direct descendant AIMACO shaped COBOL, which incorporated several of its elements:
A sample FLOW-MATIC program:
INPUT INVENTORY FILE-A PRICE FILE-B ; OUTPUT PRICED-INV FILE-C UNPRICED-INV
FILE-D ; HSP D.
COMPARE PRODUCT-NO WITH PRODUCT-NO ; IF GREATER GO TO [|OPERATION 10] ;
IF EQUAL GO TO [|OPERATION 5] ; OTHERWISE GO TO [|OPERATION 2].
TRANSFER A TO D.
WRITE-ITEM D.
JUMP TO [|OPERATION 8].
TRANSFER A TO C.
MOVE UNIT-PRICE TO UNIT-PRICE .
WRITE-ITEM C.
READ-ITEM A ; IF END OF DATA GO TO [|OPERATION 14].
JUMP TO [|OPERATION 1].
READ-ITEM B ; IF END OF DATA GO TO [|OPERATION 12].
JUMP TO OPERATION 1.
SET OPERATION 9 TO GO TO OPERATION 2.
JUMP TO OPERATION 2.
TEST PRODUCT-NO AGAINST ; IF EQUAL GO TO [|OPERATION 16] ;
OTHERWISE GO TO [|OPERATION 15].
REWIND B.
CLOSE-OUT FILES C ; D.
STOP.
Sample Notes
  1. Note that this sample includes only the executable statements of the program, the section. The record fields and would have been defined in the section, which did not use English-like syntax.
  2. Files are referred to by the letter at the end of the FILE-LETTER. Example: FILE-A is referred to later just by A and is for ease of reference in following code.
  3. Operations are numbered in an unbroken sequence from 0..n and are performed in that order unless a statement to the contrary is reached/made .
  4. The highest numbered operation is the one that stops the program.
  5. A much more detailed overview of FLOW-MATIC is available in the manual entitled, FLOW-MATIC PROGRAMMING SYSTEM