[Haskell-cafe] Data constructors versus types

[Peter Verswyvelen]

I know nothing about theoretical computer science, but I was wondering
if it possible to forget about types, and just keep the concept of data
constructors, and have an analyzer determine correctness of the code and
"staticness" of the data?

Basically this is what SCHEME does no? Doesn't SCHEME have static whole
program analyzers to remove the overhead of the "symbol tags" and check
correctness of a program (Stalin, Petit-Scheme, ...)?

What are to pros/contras?

Thank you,
Peter