Can we also get some feedback on specialization, please?

Richard Warburton richard.warburton at
Wed Jan 7 22:38:32 UTC 2015

Hi Ivan,

We, from the Bulgarian JUG are also planning to do a hackathon on this.
> Most probably it will be on January 29th (just before FOSDEM). We'll update
> the VMs we already have and will also, as usual, write some blogs.

There's probably a pretty steep learning curve, but best of luck with your
efforts. I imagine it'll be helpful.

As I am taking care of presenting this to my fellows here in Bulgaria and
> as I am poorly prepared in the language and type theory, would you please
> tell me where can I read more what is a compiler fiction, specialization vs
> erasure vs reification and all the things that are discussed in the various
> thread an in the state of specialization paper? Sorry for the stupid
> question, but I really want to get my folks here (including myself) up to
> speed.

There are no stupid questions. Actually that's a lie - but these aren't
stupid questions.

Afaict in this case the term "Compiler Fiction" is being used to denote a
concept which exists at some level of abstraction but not at a lower level.
For example you could describe a while loop as a compiler fiction because
when you hit bytecode control flow is represented by gotos. Obviously
removing some abstractions is a good thing and whilst others tend to leak
through to the source of the translation. You'll have to make your own mind
up as to whether adding or not adding an Any type is a good idea or a bad

As to specialization - there are solid links from I don't really know much more
than reading those topics. Erasure and generics have quite a few general
articles which Google is more adequately qualified to index than I am.

If you are finding it difficult to understand the documents linked but want
to understand them. For example if you don't know what a "subtyping
relationship" is then I don't have an easy answer for you. Years ago I
bought and read which is an
excellent book, but not an easy or quick read. I've also forgotten most of
it though - so I do have to ask stupid questions from time to time myself
;) It would be good if someone wrote a quick introduction to this kind of
thing for professional developers.

*I don't think any of that should stop you from running a hackday. Just
write some code that looks like it should work and then email the list
saying what was confusing or broken.*


  Richard Warburton
  @RichardWarburto <>

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