Currently, there are two open source alternative implementations of Turing : Open Turing, an open source version of the original interpreter, and TPlus, a native compiler for the concurrent systems programming language variant Turing Plus.
22.
"System Programming Language " ( SPL ) is also the name of a specific language on the HP 3000 computer series, used for its operating system HP Multi-Programming Executive, and other parts of its system software.
23.
While Turing is a completely " safe " language, providing no direct access to the hardware, its extension, object-oriented Turing, includes concurrency, exception handling, objects, classes and inheritance, and systems programming language features; it is an alternative to languages like C and Modula.
24.
BCPL ( for " Basic CPL ", although originally " Bootstrap CPL " ), was a much simpler language based on CPL intended primarily as a systems programming language, particularly for writing compilers; it was first implemented in 1967, prior to CPL's first implementation.
25.
The terms were coined by Frank DeRemer and Hans Kron in their 1975 paper " Programming-in-the-large versus programming-in-the-small " A similar, later distinction is Ousterhout's dichotomy between " system programming languages " ( for components ) and " scripting languages " for glue code, connecting components.
26.
"' Ousterhout's dichotomy "'is computer scientist John Ousterhout's categorization that high-level programming languages tend to fall into two groups, each with distinct properties and uses : " system programming languages " and " scripting languages " compare programming in the large and programming in the small.
27.
Mesa was developed on the Xerox Alto, one of the first personal computers with a graphical user interface, however most of the Alto's system software was written in BCPL . Mesa was the system programming language of the later Xerox Star workstations, and for the GlobalView desktop environment.
28.
The earliest versions of the system used only HP's proprietary SPL systems programming language and BASIC . These System 3000s used a command line interpreter, with a three-level hierarchical file system, and utilities such as compilers would resemble " run fortran . pub . sys " rather than allowing programs to be run as keyword commands.
29.
B started off as a syntactically changed variant of the systems programming language BCPL, a simplified ( and typeless ) version of CPL . In what has been described as a " strip-down " process, the and and or operators of BCPL were replaced with & and | ( which would later become & & and | |, respectively . ).
