PL/I
Programming Language One, often referred to as PL / I ( PL / 1 PL1 or PLI) abbreviated is a programming language that was developed in the 1960s by IBM. The term PL / 1 is common, especially in Germany.
History of development
Originally PL / I was developed as a general programming language for all applications under the name of NPL (New Programming Language). An attempt was made to take advantage of all hitherto existing high-level languages (in particular, Algol, Fortran and COBOL) to unite. Similarly, there was a goal, the dynamic memory management of assembler simplifies in PL / I integrate.
Properties
Critics of the language imputed PL / I, it was unfortunately only able to combine the disadvantages of the different models. In scientific and technical programmers, it was considered a commercial, commercial users in the natural sciences and technology. Trailers point to the advantages:
- Syntax with free format
- Keywords are not case -insensitive
- Many built-in functions
- Supports structured programming
- Supports recursive programming
- Datatypes are hardware independent
- Dynamic memory management
- Event handling
Implementations
PL / I was and still is in some large IBM users home language. Multics was written in PL / I.
Descendants of the PL / I are PL / M ( for microcomputers; major parts of CP / M were in PL / M written ) and PL / S ( IBM internal programming language for system software).
PL / I is used primarily on IBM mainframes, but there are also versions for Windows, OS / 2, AIX, and other Unix variants.
Compared to the later-developed languages such as Pascal characterizes the whole of PL / I language family ( as it did the precursor of the ALGOL - Zoo), that data structures could be specified as concrete elements, but there were virtually no language elements for the definition of structure types. In the latest generation of PL / I of the company IBM Enterprise PL / I, and abstract data types can be used.
Program Example Hello World
Hello: proc options (main ); put list ( 'Hello world! '); Hi end; see also