Pastel (programming language)
# Pastel (programming language)

Pastel is an extended version of the Pascal programming language, created in c. 1982 for Amber, an operating system for the S-1 supercomputer project at Lawrence Livermore National Laboratory in California. The Pastel compiler was the inspiration for Richard Stallman's GNU C compiler.

Pastel was conceived by Jeffrey M. Broughton, then Project Engineer in charge of compilers and operating system software for the S-1 project, because of dissatisfaction with the PL/1 language in which Amber was being implemented. The language was named Pastel ("an off-color Pascal").

Compared with Pascal compilers of that period, Pastel's features included:

* Improved type definition
* Parametric types
* Explicit packing and allocation control
* Additional parameter passing modes
* Additional control constructs
* Set iteration
* Loop-exit form
* Return statement
* Module definition
* Exception handling
* General enhancements
* Conditional boolean operations
* Constant expressions
* Variable initialization
