Clarion was created by Bruce Barrington, one of the founders of healthcare firm "HBO & Company" (later acquired by McKesson Corporation, ) and a small team of developers. The first release of the Clarion language was a DOS product named Clarion 1.0 and was first released in April 1986. Three main Clarion products exist: Professional Edition, Enterprise Edition, and. Many templates have been written by various developers: some are offered as commercial add-ons, and some are free. The templates (from which the code is generated) are provided in source form and developers are free to create their own templates. This mixing of template code and generated code allows the template settings to be updated, and the code regenerated, without loss of the embedded code. This process of embedding code can be done while viewing the surrounding generated code. If the templates are used to generate code, then programmers are able to inject their own code into the generated code to alter, or extend, the functions offered by the template layer. It is possible to create programs fully at the code level ( the so-called 3 Lager), bypassing all code generation facilities. This generation layer is sometimes referred to as 4GL programming. The generator then turns this higher level into code, which in turn is then compiled and linked using a normal compiler and linker.
The IDE provides code generation facilities via a system of templates which allow programmers to describe the program from an abstract level higher than code statements. The Clarion development environment ( IDE) runs on the Clarion language. It is compatible with indexed sequential access method ( ISAM), Structured Query Language ( SQL), and ActiveX Data Objects ( ADO) data access methods, reads and writes several flat file desktop database formats including ASCII, comma-separated values ( CSV), DOS (binary), FoxPro, Clipper, dBase, and some relational databases via ODBC, Microsoft SQL Server, Sybase SQL Anywhere, and Oracle Database through the use of accelerated native database drivers, and XML, Clarion can be used to output to HTML, XML, plain text, and Portable Document Format ( PDF), among others. Clarion is a commercial, proprietary, fourth-generation programming language ( 4GL), multi-paradigm, programming language and integrated development environment ( IDE) from SoftVelocity used to program database applications.
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