Fourth-generation programming language
As a fourth generation language or short 4GL programming languages or programming environments is called the fourth generation. These are aimed at quickly - to write for a specific application functions or entire applications - with as few lines of code.
The term 4GL is not precisely defined and is used primarily for marketing purposes. The common main aim of all 4GL, however, is to achieve the same functionality with less code compared with third-generation languages . The term was often used in the 1980s, often fixed to a particular topic, application-specific script or query languages such as SQL are called 4GL languages. Later the term Rapid Application Development (RAD ) has been applied with overlapping semantics. It now appears more and more that application-specific scripting languages are just the input for a 4GL language. That is, the actual 4GL is used to specify a system that in turn can interpret a specific script language. So-called parser generators such as X2X allow for any purpose to define its own scripting language and transform the scripts created with it in the source code of a high-level language of the third generation. As an application-specific scripting language essentially always used to define a specific model of a specific topic, it is called here lately, increasingly, from model- centric software development and model- driven software development.
In the first third-generation languages (eg, Fortran, Pascal, and C) was the introduction of standardized control structures in the foreground. This was followed by the creation of extensive libraries with additional modules, such as often occur in specialized applications. The following object-oriented programming languages such as C and Java made great improvements in the software structure with itself. At the same time created more and more graphical editors that have been optimized in their semantics for certain applications, to simplify the access to the associated libraries. In most successful cases, there was a so-called visual language. Since this could not be clearly assigned to the high third-generation languages , these were often already called 4GL language, which was not a distinction between the actual "language" and the system that can interpret such language.
The term 4GL was highly touted by James Martin. He used it first in his 1982 book Application Development Without Programmers ( " application development without programmers "). This interpretation comes but only in recent times with the model-driven software development really apply.
- Reducing the development effort through the use of comprehensible, application-oriented paradigms.
- Better maintainability and extensibility of the programs through better readability and user-friendly presentation
- As a result, a reduction in development time and cost
- Report generators
- Entry form generators
- Total systems capable of managing the details of CASE systems and generate input generators and further specification of process logic all systems and report. An example of this is the tool of Information Engineering James Martin, which allows to capture the results of system analysis and system design (in the form of data flow diagrams, entity-relationship diagrams and entity life-cycle diagrams). This then hundreds of thousands of COBOL program lines were generated.
- Generation of parts or entire software systems from application-specific models of the industry, eg with AUTOSAR.
- Programming language