Software Language Engineering - Text Processing Language Design, Implementation, Evaluation Methods

Programming languages drive most if not all of modern problem-solving using computational methods and power. Research into new programming languages and techniques is essential because it makes the design, implementation, and application of automation to general or particular problem-solving ever easier, more accessible, and more performant. GPLs typically are designed to be purely domain agnostic---meaning they can be applied in any field, for any problem kind. However, this normally also makes them hard and difficult to use in problems where non-programmers or even experts with little or no GPL programming skills are required to leverage programmatic problem-solving capabilities, which is why DSLs come into play; they are generally more fine-tuned toward improving human productivity and performance than that of the machine, while making solving particular, domain-oriented problems simpler. In this paper, we review the literature concerning how to design and then fully implement a new DSL, with a special focus on a DSL for generic problem-solving leveraging Text Processing methods---a Text Processing Language (TPL). We consider leveraging the Design Research paradigm as a systematic framework for guiding research into the development of new TPLs. We present for the first time, a new unifying theory concerning general, but also TPL-specific language engineering theory and guiding frameworks---UPLT, PLEF \& PLEf. With a re-introduction of the SOE framework, we consider quantitative and qualitative evaluation of software languages, with specific focus on programming languages. Finally, we highlight identified pending problems for future theoretical and pragmatic research into the field of language engineering, especially with a focus on TPLs.