PL-6 is a discontinued system programming language based on PL/I. PL-6 was developed by Honeywell, Inc. in the late 1970s as part of the project to develop the CP-6 operating system.
Contents
Data types
PL-6 has no provision for floating point data.
Aggregates
Arrays were one dimensional and zero-based, with the zero specified explicitly. For example, DCL x (0:4) SBIN; declares an array of five signed 36-bit integers. The elements were numbered x(0), x(1),...,x(4).
Structures were also supported. For example:
DCL 1 struct,
2 a,
3 b CHAR(3),
3 * CHAR(1),
2 c CHAR(4);
declares a structure named struct consisting to two elements: a minor structure a consisting of a three-character field b and an unnamed one-character element ("*" indicates the element is unnamed), and a four-character element c.
The top level of the structure had to be 1, and the remaining levels 2–10, if used, had to be specified in order with no levels skipped.