See e.g. Applicative instance in Data.Vect. This allows implementations
to use implicits at run time (by default, they'd be 0 multiplicity so
erased, but it might be useful to have an index available at run time).
At the moment, the parser requires implicits to be given before
constraints. Ideally it should be possible to give them in any order.
I'll come back to this.
This makes it easier for more complicated packages (e.g. network, which
needs to install a C shared library) to know where to put things without
having to work out the prefix themselves.
Since they'll be incompatible between different Idris2 versions, this
helps protect against importing the wrong thing by mistake. Also, it
means the canonical place for the version number is now the top level
Makefile.
You'll need to delete src/YafflePaths.idr before rebuilding, since it's
now generated slightly differently.
This is so that we can put other build artefacts (e.g. executables) in
properly organised subdirectories of build, e.g. build/bin/chez,
build/bin/js, etc.
Functions can be declared as %foreign with a list of calling
conventions, which a backend will work through until it finds one it can
understand. Currently implemented only in Chez backend. If this works
out, I'll implement it for Racket too, and remove the old primitive
functions.
There's a bit more boiler plate here than before, but it has the benefit
of being more extensible and portable between different back ends.
Some examples, pending proper documentation:
%foreign "C:puts,libc" "scheme:display"
putline : String -> PrimIO ()
%foreign "C:exp, libm.so.6, math.h"
fexp : Double -> Double
%foreign "C:initscr, ncurses_glue.so, ncurses.h"
prim_initscr : PrimIO ()
Since it's just to check that it's built successful and we can send a
message back and forth, remove the diagnostic message that might come
out in a different order depending on scheduling.
Lots were missing, and some were export, which should probably be public
export because the nature of Vect is that it could commonly be used in
types.
Fixes#13
This is part of what we used to have in Enum but I think it's better to
separate the two. Added implementations for Nat, and anything in
Integral/Ord/Neg, so that we get range syntax (at least when its
implemeted) for the most useful cases.
This required a small change to auto implicit search (and I'm still not
sure about this). Now search arguments right to left, because solving
later arguments may resolve earlier arguments by unification and this
can happen in particular when chasing parent interfaces (which may have
fewer parameters).
Now supports with applications on the RHS when auto implicits are
involved. Auto implicit bound names in patterns now become searches on
the rhs in a with-application (I should write this construct up properly
in a paper some time!)
We use this to decide whether a determining argument is satisfied or not
for unbound implicits. We can tell from the name, which would be a PV,
but this way relies on fewer assumptions.
Elaborate via either === (homogeneous equality) or ~=~ (heterogeneous
equality) both of which are synonyms for Equal. This is to get the Idris
1 behaviour that equality is homogeneous by default to reduce the need
for type annotations, but heterogeneous if that doesn't work.
Like in delayed ambiguity resolution, we need to reevaluate the target
type because it might have changed - and that's why we delayed in the
first place!
This has shown up a problem with 'case' which is hard to fix - since it
works by generating a function with the appropriate type, it's hard to
ensure that let bindings computational behaviour is propagated while
maintaining appropriate dependencies between arguments and keeping the
let so that it only evaluates once. So, I've disabled the computational
behaviour of 'let' inside case blocks. I hope this isn't a big
inconvenience (there are workarounds if it's ever needed, anyway).
Also fix a bug where the elaborator state wasn't updated on completing
the delayed elaborator, which could cause issues with implicitly bound
names in particular.
Need to run delayed elaborators before binding implicits, since there
might be some inside the delayed elaborator. Also reorganise TTC
implementations so they're all in one place.