Generating type annotations by tracing execution runs

[Paul Rubin]

Chris Angelico <rosuav at gmail.com> writes:
>> As the code, such as a test suite, runs, the types of arguments and
>> return values...
> Sounds to me like a type inference system. Can be pretty handy in some
> codebases.

I haven't tried it out yet but it sounds more like the type extraction
part of a JIT compiler, i.e. the types are collected from actual
execution traces rather than statically.  I think of "type inference" as
meaning syntactic inference at compile time.