move idris version to orig and newt version to src.

Development is being done on the newt version now.
This commit is contained in:
2025-02-15 16:36:29 -08:00
parent 829c5d5143
commit 3c2615ecc1
52 changed files with 86 additions and 22 deletions

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orig/Lib/Eval.idr Normal file
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module Lib.Eval
import Lib.Types
import Lib.TopContext
import Data.IORef
import Data.Fin
import Data.List
import Data.SnocList
import Data.Vect
import Data.SortedMap
export
eval : Env -> Mode -> Tm -> M Val
-- REVIEW everything is evalutated whether it's needed or not
-- It would be nice if the environment were lazy.
-- e.g. case is getting evaluated when passed to a function because
-- of dependencies in pi-types, even if the dependency isn't used
public export
infixl 8 $$
public export
($$) : {auto mode : Mode} -> Closure -> Val -> M Val
($$) {mode} (MkClosure env tm) u = eval (u :: env) mode tm
export
vapp : Val -> Val -> M Val
vapp (VLam _ _ _ _ t) u = t $$ u
vapp (VVar fc k sp) u = pure $ VVar fc k (sp :< u)
vapp (VRef fc nm def sp) u = pure $ VRef fc nm def (sp :< u)
vapp (VMeta fc k sp) u = pure $ VMeta fc k (sp :< u)
vapp t u = error' "impossible in vapp \{show t} to \{show u}\n"
export
vappSpine : Val -> SnocList Val -> M Val
vappSpine t [<] = pure t
vappSpine t (xs :< x) = do
rest <- vappSpine t xs
vapp rest x
lookupVar : Env -> Nat -> Maybe Val
lookupVar env k = let l = length env in
if k > l
then Nothing
else case getAt (lvl2ix l k) env of
Just v@(VVar fc k' sp) => if k == k' then Nothing else Just v
Just v => Just v
Nothing => Nothing
-- hoping to apply what we got via pattern matching
export
unlet : Env -> Val -> M Val
unlet env t@(VVar fc k sp) = case lookupVar env k of
Just tt@(VVar fc' k' sp') => do
debug "lookup \{show k} is \{show tt}"
if k' == k then pure t else (vappSpine (VVar fc' k' sp') sp >>= unlet env)
Just t => vappSpine t sp >>= unlet env
Nothing => do
debug "lookup \{show k} is Nothing in env \{show env}"
pure t
unlet env x = pure x
export
tryEval : Env -> Val -> M (Maybe Val)
tryEval env (VRef fc k _ sp) = do
top <- get
case lookup k top of
Just (MkEntry _ name ty (Fn tm)) =>
catchError (
do
debug "app \{show name} to \{show sp}"
vtm <- eval [] CBN tm
debug "tm is \{render 90 $ pprint [] tm}"
val <- vappSpine vtm sp
case val of
VCase _ _ _ => pure Nothing
VLetRec _ _ _ _ _ => pure Nothing
v => pure $ Just v)
(\ _ => pure Nothing)
_ => pure Nothing
tryEval _ _ = pure Nothing
-- Force far enough to compare types
export
forceType : Env -> Val -> M Val
forceType env (VMeta fc ix sp) = do
meta <- lookupMeta ix
case meta of
(Unsolved x k xs _ _ _) => pure (VMeta fc ix sp)
(Solved _ k t) => vappSpine t sp >>= forceType env
forceType env x = do
Just x' <- tryEval env x
| _ => pure x
forceType env x'
evalCase : Env -> Mode -> Val -> List CaseAlt -> M (Maybe Val)
evalCase env mode sc@(VRef _ nm _ sp) (cc@(CaseCons name nms t) :: xs) = do
top <- get
if nm == name
then do
debug "ECase \{show nm} \{show sp} \{show nms} \{showTm t}"
go env (sp <>> []) nms
else case lookup nm top of
(Just (MkEntry _ str type (DCon k str1))) => evalCase env mode sc xs
-- bail for a stuck function
_ => pure Nothing
where
go : Env -> List Val -> List String -> M (Maybe Val)
go env (arg :: args) (nm :: nms) = go (arg :: env) args nms
go env args [] = do
t' <- eval env mode t
Just <$> vappSpine t' ([<] <>< args)
go env [] rest = pure Nothing
-- REVIEW - this is handled in the caller already
evalCase env mode sc@(VVar fc k sp) alts = case lookupVar env k of
Just tt@(VVar fc' k' sp') => do
debug "lookup \{show k} is \{show tt}"
if k' == k
then pure Nothing
else do
val <- vappSpine (VVar fc' k' sp') sp
evalCase env mode val alts
Just t => do
val <- vappSpine t sp
evalCase env mode val alts
Nothing => do
debug "lookup \{show k} is Nothing in env \{show env}"
pure Nothing
evalCase env mode sc (CaseDefault u :: xs) = Just <$> eval (sc :: env) mode u
evalCase env mode sc cc = do
debug "CASE BAIL sc \{show sc} vs \{show cc}"
debug "env is \{show env}"
pure Nothing
-- TODO maybe add glueing
eval env mode (Ref fc x def) = pure $ VRef fc x def [<]
eval env mode (App _ t u) = do
t' <- eval env mode t
u' <- eval env mode u
vapp t' u'
eval env mode (UU fc) = pure (VU fc)
eval env mode (Erased fc) = pure (VErased fc)
eval env mode (Meta fc i) = do
meta <- lookupMeta i
case meta of
(Unsolved _ k xs _ _ _) => pure $ VMeta fc i [<]
(Solved _ k t) => pure $ t
eval env mode (Lam fc x icit rig t) = pure $ VLam fc x icit rig (MkClosure env t)
eval env mode (Pi fc x icit rig a b) = do
a' <- eval env mode a
pure $ VPi fc x icit rig a' (MkClosure env b)
eval env mode (Let fc nm t u) = do
t' <- eval env mode t
u' <- eval (VVar fc (length env) [<] :: env) mode u
pure $ VLet fc nm t' u'
eval env mode (LetRec fc nm ty t u) = do
ty' <- eval env mode ty
t' <- eval (VVar fc (length env) [<] :: env) mode t
u' <- eval (VVar fc (length env) [<] :: env) mode u
pure $ VLetRec fc nm ty' t' u'
-- Here, we assume env has everything. We push levels onto it during type checking.
-- I think we could pass in an l and assume everything outside env is free and
-- translate to a level
eval env mode (Bnd fc i) = case getAt i env of
Just rval => pure rval
Nothing => error fc "Bad deBruin index \{show i}"
eval env mode (Lit fc lit) = pure $ VLit fc lit
eval env mode tm@(Case fc sc alts) = do
-- TODO we need to be able to tell eval to expand aggressively here.
sc' <- eval env mode sc
sc' <- unlet env sc' -- try to expand lets from pattern matching
sc' <- forceType env sc'
vsc <- eval env mode sc
vcase <- evalCase env mode sc' alts
pure $ fromMaybe (VCase fc vsc alts) vcase
export
quote : (lvl : Nat) -> Val -> M Tm
quoteSp : (lvl : Nat) -> Tm -> SnocList Val -> M Tm
quoteSp lvl t [<] = pure t
quoteSp lvl t (xs :< x) = do
t' <- quoteSp lvl t xs
x' <- quote lvl x
pure $ App emptyFC t' x'
quote l (VVar fc k sp) = if k < l
then quoteSp l (Bnd fc (lvl2ix l k )) sp -- level to index
else error fc "Bad index in quote \{show k} depth \{show l}"
quote l (VMeta fc i sp) = do
meta <- lookupMeta i
case meta of
(Unsolved _ k xs _ _ _) => quoteSp l (Meta fc i) sp
(Solved _ k t) => vappSpine t sp >>= quote l
quote l (VLam fc x icit rig t) = do
val <- t $$ VVar emptyFC l [<]
tm <- quote (S l) val
pure $ Lam fc x icit rig tm
quote l (VPi fc x icit rig a b) = do
a' <- quote l a
val <- b $$ VVar emptyFC l [<]
tm <- quote (S l) val
pure $ Pi fc x icit rig a' tm
quote l (VLet fc nm t u) = do
t' <- quote l t
u' <- quote (S l) u
pure $ Let fc nm t' u'
quote l (VLetRec fc nm ty t u) = do
ty' <- quote l ty
t' <- quote (S l) t
u' <- quote (S l) u
pure $ LetRec fc nm ty' t' u'
quote l (VU fc) = pure (UU fc)
quote l (VRef fc n def sp) = quoteSp l (Ref fc n def) sp
quote l (VCase fc sc alts) = do
sc' <- quote l sc
pure $ Case fc sc' alts
quote l (VLit fc lit) = pure $ Lit fc lit
quote l (VErased fc) = pure $ Erased fc
-- Can we assume closed terms?
-- ezoo only seems to use it at [], but essentially does this:
export
nf : Env -> Tm -> M Tm
nf env t = eval env CBN t >>= quote (length env)
export
nfv : Env -> Tm -> M Tm
nfv env t = eval env CBV t >>= quote (length env)
export
prvalCtx : {auto ctx : Context} -> Val -> M String
prvalCtx v = do
tm <- quote ctx.lvl v
pure $ interpolate $ pprint (toList $ map fst ctx.types) tm
export
zonk : TopContext -> Nat -> Env -> Tm -> M Tm
zonkBind : TopContext -> Nat -> Env -> Tm -> M Tm
zonkBind top l env tm = zonk top (S l) (VVar (getFC tm) l [<] :: env) tm
-- I don't know if app needs an FC...
appSpine : Tm -> List Tm -> Tm
appSpine t [] = t
appSpine t (x :: xs) = appSpine (App (getFC t) t x) xs
-- REVIEW When metas are subst in, the fc point elsewhere
-- We might want to update when it is solved and update recursively?
-- For errors, I think we want to pretend the code has been typed in place
tweakFC : FC -> Tm -> Tm
tweakFC fc (Bnd fc1 k) = Bnd fc k
tweakFC fc (Ref fc1 nm x) = Ref fc nm x
tweakFC fc (UU fc1) = UU fc
tweakFC fc (Meta fc1 k) = Meta fc k
tweakFC fc (Lam fc1 nm icit rig t) = Lam fc nm icit rig t
tweakFC fc (App fc1 t u) = App fc t u
tweakFC fc (Pi fc1 nm icit x t u) = Pi fc nm icit x t u
tweakFC fc (Case fc1 t xs) = Case fc t xs
tweakFC fc (Let fc1 nm t u) = Let fc nm t u
tweakFC fc (LetRec fc1 nm ty t u) = LetRec fc nm ty t u
tweakFC fc (Lit fc1 lit) = Lit fc lit
tweakFC fc (Erased fc1) = Erased fc
-- TODO replace this with a variant on nf
zonkApp : TopContext -> Nat -> Env -> Tm -> List Tm -> M Tm
zonkApp top l env (App fc t u) sp = do
u' <- zonk top l env u
zonkApp top l env t (u' :: sp)
zonkApp top l env t@(Meta fc k) sp = do
meta <- lookupMeta k
case meta of
(Solved _ j v) => do
sp' <- traverse (eval env CBN) sp
debug "zonk \{show k} -> \{show v} spine \{show sp'}"
foo <- vappSpine v ([<] <>< sp')
debug "-> result is \{show foo}"
tweakFC fc <$> quote l foo
(Unsolved x j xs _ _ _) => pure $ appSpine t sp
zonkApp top l env t sp = do
t' <- zonk top l env t
pure $ appSpine t' sp
zonkAlt : TopContext -> Nat -> Env -> CaseAlt -> M CaseAlt
zonkAlt top l env (CaseDefault t) = CaseDefault <$> zonkBind top l env t
zonkAlt top l env (CaseLit lit t) = CaseLit lit <$> zonkBind top l env t
zonkAlt top l env (CaseCons name args t) = CaseCons name args <$> go l env args t
where
go : Nat -> Env -> List String -> Tm -> M Tm
go l env [] tm = zonk top l env t
go l env (x :: xs) tm = go (S l) (VVar (getFC tm) l [<] :: env) xs tm
zonk top l env t = case t of
(Meta fc k) => zonkApp top l env t []
(Lam fc nm icit rig u) => Lam fc nm icit rig <$> (zonk top (S l) (VVar fc l [<] :: env) u)
(App fc t u) => do
u' <- zonk top l env u
zonkApp top l env t [u']
(Pi fc nm icit rig a b) => Pi fc nm icit rig <$> zonk top l env a <*> zonkBind top l env b
(Let fc nm t u) => Let fc nm <$> zonk top l env t <*> zonkBind top l env u
(LetRec fc nm ty t u) => LetRec fc nm <$> zonk top l env ty <*> zonkBind top l env t <*> zonkBind top l env u
(Case fc sc alts) => Case fc <$> zonk top l env sc <*> traverse (zonkAlt top l env) alts
UU fc => pure $ UU fc
Lit fc lit => pure $ Lit fc lit
Bnd fc ix => pure $ Bnd fc ix
Ref fc ix def => pure $ Ref fc ix def
Erased fc => pure $ Erased fc