D "string mixins" allow to insert any string as code, usually the result of a compile-time computation. Some use cases: - make repetitive code shorter [1]. Th

D "string mixins" allow to insert any string as code, usually the result of a compile-time computation. Some use cases: - make repetitive code shorter [1]. Think the C preprocessor but after the parsing stage. - operator overloading is a single template function parameterized by a compile-time string. This more or less requires using string mixins [2]. - [edit] raleks's comment has better examples [3]. Overall string mixins feel a bit dirty but you get used to it. D also has "template mixins" which do not escape parsing prior instantiation. D mixins are neither like Scala mixins nor Ruby mixins. [1] https://github.com/p0nce/gfm/blob/master/math/easing.d#L64 https://github.com/p0nce/gfm/blob/master/math/easing.d#L64. [2] https://github.com/Dav1dde/gl3n/blob/master/gl3n/linalg.d#L2232 https://github.com/Dav1dde/gl3n/blob/master/gl3n/linalg.d#L2... [3] http://news.ycombinator.com/item?id=4456422 http://news.ycombinator.com/item?id=4456422