What is Expressiveness in a Computer Language

[Marshall]

Nice post! One question:

Anton van Straaten wrote:
>
> 3.  A really natural term to refer to types which programmers reason
> about, even if they are not statically checked, is "latent types".  It
> captures the situation very well intuitively, and it has plenty of
> precedent -- e.g. it's mentioned in the Scheme reports, R5RS and its
> predecessors, going back at least a decade or so (haven't dug to check
> when it first appeared).

Can you be more explicit about what "latent types" means?
I'm sorry to say it's not at all natural or intuitive to me.
Are you referring to the types in the programmers head,
or the ones at runtime, or what?


Marshall