Foreign language interfaces by code migration

Abstract

A foreign function interface (FFI) is a classical abstraction used for interfacing a programming language with another foreign language to reuse its libraries. This interface is important for a new (or non prevailing) language because it lacks libraries and thus needs to borrow libraries written in a foreign language when the programmer develops a practical application in that new language. However, a modern library often exploits unique language mechanisms of the implementation language. This makes the use of the library difficult through a simple function call from that new language. This paper presents our approach to this problem. We use an embedded domain specific language (DSL), which is designed to resemble the foreign language, and migrate the DSL code to access to the library written in the foreign language. This paper also presents our framework Yadriggy for developing the DSL from Ruby to a foreign language environment. The framework supports DSL-specific syntax checking for the migrated DSL code.