iCoLa⁺: An extensible meta-language with support for exploratory language development

Programming languages providing high-level abstractions can increase a programmers’ productivity and the safety of a program. Language-oriented programming is a paradigm in which domain-specific languages are developed to solve problems within specific domains with (high-level) abstractions relevant to those domains. However, language development involves complex design and engineering processes. These processes can be simplified by reusing (parts of) existing languages and by offering language-parametric tooling. In this paper we present iCoLa⁺, an extensible meta-language implemented in Haskell supporting incremental (meta-)programming based on reusable components. We demonstrate iCoLa⁺ through the construction of the Imp, SIMPLE, and MiniJava languages via the composition and restriction of language fragments, demonstrate the variability of our approach through the construction of several languages using a fixed-set of operators, and demonstrate the different forms of extensions possible in iCoLa⁺.