Clarion (programming language)

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Clarion is an object-oriented 4GL - Programming language and integrated development environment (IDE) for developing database applications, and is attributable to the application-oriented programming languages. The product is being developed and distributed by Softvelocity .


In contrast to many other programming languages, Clarion has its own template language which is used to generate verified source code. A large part of the application development with the software therefore takes place through the use of templates. These contain both the interface to the programmer (e.g. which tables and fields should be displayed in a browse window) and the rules for code generation. The Clarion IDE contains the generator which processes the templates and inputs of the programmer and finally generates the source code to be compiled. Clarion includes a RAD ( Rapid Development Tool ) that enables the developer to develop the basic structure of an application with just a few clicks of the mouse using wizards (templates).

The data dictionary (data dictionary) is the focus of the software, in which u. a. the database tables and their attributes are defined. In the AppGen (application generator, application generator), complete applications can be created around the defined tables with just a few clicks of the mouse. The system relies on the aforementioned templates and generates source code, which is then automatically compiled into executable programs (EXE) or libraries (DLL). The APP file contains the complete definition of the application and can be expanded at key points with handwritten source code. Changes and enhancements are made in the APP file, which is completely or (if possible) only partially recreated as a source every time.

The Clarion 4GL language is a special database-neutral programming language that was specially written for business applications. Other applications can also be created with the software. One advantage of the software is that it generates executable programs (EXE files) for which no further license fees are due and which are network-compatible without further ado. The software can virtually access all data through a combination of ODBC / ADO and natural database drivers. Otherwise, web applications can also be created with Clarion. The scope of delivery of the "Enterprise Edition" includes templates for HTTP sockets, XML and JSON objects. In addition, there are extensive third-party libraries such as "Nettalk" from CapeSoft or the "Clarion Handy Tools CHT" from Gus Creces, with which web servers and clients, mail servers and clients and FTP clients can be created.


The software goes back to an idea by Bruce Barrington , who founded Clarion Software Corporation in 1982. In 1986 Clarion 1.0 was released. In 1992 Clarion Software merged with Jensen and Partners International , the compiler forge of Niels Jensen , one of the founders of Borland , to form TopSpeed ​​Corporation . In May 2000, the Clarion line of products was sold to SoftVelocity, Inc.

Clarion for Windows was a further development of the older DOS version. Applications created with DOS could easily be ported to Windows.

Version 6.3 of the software was distributed in March 2007. The development environment is still operated in 16-bit mode, only the actual compilers are 32-bit. The 16-bit IDE results in problems especially when using current Windows technologies (such as ActiveX , OLE DB , OCX , COM , DCOM , etc.). Both 16- and 32-bit applications can be created on the same code base .

The current version 11 has a 32-bit development environment (IDE) based on .NET , with which Clarion applications from earlier versions can also be managed and further developed.

Code example

 Relate:PERSON.Open()                                        ! Öffnen einer zuvor deklarierten Tabelle
 PERSON:Name = 'Müller'                                      ! Zuweisung einer Zeichenkette
 if Access:PERSON.fetch(PERSON:KeyName) = Level:Benign then  ! Datensatz über einen Schlüssel lesen
   message('Name gefunden!')                                 ! wenn erfolgreich, dann Meldung
 Relate:PERSON.Close                                         ! Tabelle schließen

File formats and database drivers

  1. ADO
  2. ASCII
  3. Clipper
  4. dBASE
  5. DOS - ( binary file )
  6. IBM DB2
  7. In- Memory Database driver (IMDD)
  8. Microsoft SQL Server
  9. ODBC
  10. Oracle
  11. Pervasive SQL ( Btrieve )
  12. SQL Anywhere
  13. SQLite
  14. TPS and Clarion 2.1 (Clarion's own formats)

See also

Web links