Composition of Languages Embedded in Scala

Composition is amongst the major challenges faced in language engineering. Erdweg et al. offered a taxonomy for language composition. Mernik catalogued the use of the Language Definitional Framework LISA for composition sorts in that taxonomy. We produce a similar catalogue for embedded language engineering in Scala. We begin with techniques that are not specific to Scala. They are applicable in any host language with a module system and support for higher order functions. We, then, present two more techniques to examine Scala-specific language engineering. Interestingly enough, even though dealing with embedded languages, in terms of lines of code, our material is of comparable length to its LISA counterpart. Our work lends insight into Scala's serviceability for composition, as a host for embedded language engineering.