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First released in 1986, Clarion is a proprietary programming language and integrated development environment (IDE) from SoftVelocity. There are several Clarion products available.

Used in database applications, Clarion is compatible with ADO, ISAM, and SQL data access methods. It can also read and write flat-file desktop database formats, including ASCII, Clipper, CSV, dBase, DOS, FoxPro, and some relational databases through MS SQL Server, ODBC, Sybase SQL Anywhere, and Oracle. Clarion can also be used to output to HTML, PDF, XML, and plaintext.

Sitting on top of the language, the IDE offers code generation facilities through a system of templates that allow programmers to describe the program from an abstract level higher than actual code statements. This is turned into code by the generator, then compiled and linked through the use of a compiler and linker, through a process sometimes described as 4GL programming. Programs can also be created at the code level, known as the 3GL layer, bypassing the code generation facilities of the IDE.

When templates are used to generate code, programmers are able to inject their own code into the generated code for the purpose of extending or altering the functionality offered by the template layer. This can be done while viewing the surrounding generated code, allowing template settings to be updated, and code regenerated, without loss of the embedded code.

Templates are provided in source form, and developers are free to develop and share their own templates, either for free or as commercial add-ons.

Designed by Bruce Barrington, Clarion was first released as a DOS product in 1986. The designer formed Barrington Systems to release version 1.0. Barrington Systems later became Clarion International.

Version 2.0 was released as Clarion Professional Developer. CPD included a component referred to as Designer, which incorporated a data dictionary. CPD generated Clarion code based on the contents of that dictionary and a template, known as a model file. As a text file, the model file could be modified to create custom code. CPD also introduced CRUD (create, read, update, delete) code, allowing developers to enhance functionality through the insertion of code at specified points in the generated code. Also introduced with CPD were language extension modules (LEMs) to extend the language using modules compiled in other languages. LEMs were created by Clarion and third-party developers for a number of purposes, including the ability to connect to dBase, Clipper, and Paradox databases.

In 1991, Barrington began licensing compiler technology from a company known as Jensen & Partners International, which merged with Barrington's company the following year, forming TopSpeed Corporation.

TopSpeed released Clarion for Windows in 1995, including an IDE that was completely written as a Windows GUI, able to produce programs that ran under the Windows OS. Simultaneously, its DOS product was enhanced. However, by 1997, the company dropped its DOS development, at which time the "for Windows" title was omitted from the name of its Windows product.

In 2000, Clarion development came under the auspices of SoftVelocity, which is currently responsible for it. Clarion is a purely commercial product. There is no trial version. Its use requires the purchase of a license.

Historically, Clarion was one of the first 4GL programming languages.

Due to its use of templates, non-programmers can generate sophisticated databased programs while adding only minimal amounts of their own code, or without writing any at all. Code generated by templates tends to be very reliable, particularly when the templates have been in use for some time.

Topics related to the Clarion programming language are the focus of this category, including tutorials, guides, or other resources relating to the language and IDE.

 

 

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