* Only normalise a search goal if it's fast
While we do end up normalising it anyway on success, there might be
things blocking it that make the intermediate terms very big, so only do
it speculatively to see if it's quick.
* Get information about names in reflection
Currently this is only whether it's a function, or data or type
constructor. I expect more may be useful/possible.
In a 'Bind', normalise the result of the first action, rather than
quoting the HNF. This improves performance since the HNF could be quite
big when quoted back.
Ideally, we wouldn't have to quote and unquote here, and we can probably
achieve this by tinkering with the evaluator.
This has an unfortunate effect on the reflection002 test, in that the
"typed template Idris" example now evaluates too much. But, I think the
overall performance is too important for the primary motivation
behind elaborator reflection. I will return to this!
Allows quoting a term back to a TTImp. Test reflection007 shows one
possible use for this, building a reflected, type safe, representation
of an expression.
So the type of Elab now gives the expected type that's being elaborated
to, meaning that we can run 'check' in the middle of scripts and use the
result.
Get the names of local variables. and add the ability to look up their
types.
When we get a reflected TTImp, either checking the Goal or looking up a
type, it's not impossible that there'll be some repeated binder names,
so also make sure binders are unique relative to the current context.
Ideally we'd also rename things in the environment to guarantee that all
names are unique, but we don't yet.
(This would be much easier if reflected terms were typed such that they
were well scoped, but that would also make reflection harder to use.)
If available (sometimes, say a top level expression, it might need
inferring so there'll be no goal available). Also add the ability to log
the current goal, or indeed any term.
Still all they can do is check and log. Now scripts must return
something of type TT, which is in practice a TTImp that goes to the
elaborator for final checking
Add %runElab and start on scripts, although all they can do so far is
check a term. This does gives us, sort of, "template Idris" (as
demonstrated in test reflection002)
