Clipper (programming language)
| Clipper | |
|---|---|
| Basic data
|
|
| Publishing year | 1985 |
| Current version |
CA Clipper 5.3b ( May 20, 1997 ) |
| operating system | MS-DOS |
| category | programming language |
| License | proprietary |
| www.grafxsoft.com/clipper.htm | |
Clipper is a programming language and a compiler for xBase applications that masters the programming language of the dBASE system.
history
The first version of the Clipper was released by Nantucket in the winter of 1985. In the early days it mainly supported the dBASE programming language. This was due to the fact that the developers of Clipper were originally employees of the company Ashton-Tate , which developed the extremely successful database program dBASE , with the best-known and most successful version III Plus. These developers had unsuccessfully requested a compiler that protects the code and makes it immutable.
The created applications were independent, and a dBASE license was no longer required for each workstation. After the pure dBASE language scope was originally supported, the compiler quickly developed its own life in development and unique selling points were added. The best known version was called "Summer 87". In the further course of development, the Clipper language became object-oriented (but only with four classes and without the possibility of creating your own classes) and was based on the C language . The most famous versions here were 5.01 and 5.2, while the last version 5.3 was not a great success. The main reason for this was that the DOS era had ended and Windows became the dominant operating system. However, Clipper is purely character-oriented. In version 5.3 the attempt was made to integrate graphic structures. However, these were still based on MS-DOS , not Windows .
The Nantucket company was bought by Computer Associates in 1992 . In the following period Clipper was further developed and a general database - development tool . Clipper is a high-level language , the other programming languages such as BASIC , Pascal and C is comparable. In addition, from 1994 onwards, Computer Associates further developed Clipper from a procedural language to an object-oriented language with the new independent product Visual Objects . However, Visual Objects remained a niche product that was later continued under the name "Vulcan".
The first attempt at porting Clipper programs to Windows was made by Alaska Software, a German company. The Xbase ++ product enables existing Clipper programs up to and including version 5.2 to be immediately translated into a pure 32-bit program. The range of languages has been greatly expanded, so that in addition to the pure Clipper range of functions, additional functions have been added, for example for graphic output and ActiveX. The functions from the Clipper tools are also available.
The company Multisoft delivered since 1992 the compatible development environment FlagShip , the Clipper applications (Sommer'87 to 5.3) on Linux , Unix translated or MS-Windows, and these 32-bit or 64-bit programs both textually and in a GUI Environment can run.
Since 1999 there is also a free compiler called Harbor . At the end of 2001 the xHarbour project was launched. In order to guarantee a professional and continuous further development of the project, a commercial distributor was founded in parallel. A current distribution of the entire development environment for Windows and Linux is provided here every month. In addition to the compiler and linker, it contains many additional libraries known from the Clipper world and a graphic development environment (IDE).
Examples in Clipper
A simple hello world program :
? "Hallo Welt!"
A simple database input mask:
USE kunden SHARED NEW
cls
@ 1, 0 SAY "KdNr " GET kunden->kdnr PICT "999999" VALID kunden->kdnr > 0
@ 3, 0 SAY "Name " GET kunden->name VALID !empty(kunden->name)
@ 4, 0 SAY "Adresse" GET kunden->adresse
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