diff options
Diffstat (limited to 'dhall/src/phase')
-rw-r--r-- | dhall/src/phase/typecheck.rs | 204 |
1 files changed, 89 insertions, 115 deletions
diff --git a/dhall/src/phase/typecheck.rs b/dhall/src/phase/typecheck.rs index 8f5ca8b..299997a 100644 --- a/dhall/src/phase/typecheck.rs +++ b/dhall/src/phase/typecheck.rs @@ -12,24 +12,6 @@ use crate::core::var::{Shift, Subst}; use crate::error::{TypeError, TypeMessage}; use crate::phase::{Normalized, Resolved, Type, Typed}; -macro_rules! ensure_equal { - ($x:expr, $y:expr, $err:expr $(,)*) => { - if $x.to_value() != $y.to_value() { - return Err($err); - } - }; -} - -// Ensure the provided type has type `Type` -macro_rules! ensure_simple_type { - ($x:expr, $err:expr $(,)*) => {{ - match $x.get_type()?.as_const() { - Some(dhall_syntax::Const::Type) => {} - _ => return Err($err), - } - }}; -} - fn tck_pi_type( ctx: &TypecheckContext, x: Label, @@ -417,6 +399,7 @@ fn type_last_layer( use crate::error::TypeMessage::*; use dhall_syntax::BinOp::*; use dhall_syntax::Builtin::*; + use dhall_syntax::Const::Type; use dhall_syntax::ExprF::*; use Ret::*; let mkerr = |msg: TypeMessage| TypeError::new(ctx, msg); @@ -431,19 +414,21 @@ fn type_last_layer( Value::Pi(x, tx, tb) => (x.clone(), tx.to_type(), tb.to_type()), _ => return Err(mkerr(NotAFunction(f.clone()))), }; - ensure_equal!(a.get_type()?, &tx, { - mkerr(TypeMismatch(f.clone(), tx.to_normalized(), a.clone())) - }); + if a.get_type()?.as_ref() != &tx { + return Err(mkerr(TypeMismatch( + f.clone(), + tx.to_normalized(), + a.clone(), + ))); + } Ok(RetTypeOnly(tb.subst_shift(&x.into(), &a))) } Annot(x, t) => { let t = t.to_type(); - ensure_equal!( - &t, - x.get_type()?, - mkerr(AnnotMismatch(x.clone(), t.to_normalized())) - ); + if &t != x.get_type()?.as_ref() { + return Err(mkerr(AnnotMismatch(x.clone(), t.to_normalized()))); + } Ok(RetTypeOnly(x.get_type()?.into_owned())) } Assert(t) => { @@ -460,27 +445,21 @@ fn type_last_layer( Ok(RetTypeOnly(t.to_type())) } BoolIf(x, y, z) => { - ensure_equal!( - x.get_type()?, - &builtin_to_type(Bool)?, - mkerr(InvalidPredicate(x.clone())), - ); + if x.get_type()?.as_ref() != &builtin_to_type(Bool)? { + return Err(mkerr(InvalidPredicate(x.clone()))); + } - ensure_simple_type!( - y.get_type()?, - mkerr(IfBranchMustBeTerm(true, y.clone())), - ); + if y.get_type()?.get_type()?.as_const() != Some(Type) { + return Err(mkerr(IfBranchMustBeTerm(true, y.clone()))); + } - ensure_simple_type!( - z.get_type()?, - mkerr(IfBranchMustBeTerm(false, z.clone())), - ); + if z.get_type()?.get_type()?.as_const() != Some(Type) { + return Err(mkerr(IfBranchMustBeTerm(false, z.clone()))); + } - ensure_equal!( - y.get_type()?, - z.get_type()?, - mkerr(IfBranchMismatch(y.clone(), z.clone())) - ); + if y.get_type()? != z.get_type()? { + return Err(mkerr(IfBranchMismatch(y.clone(), z.clone()))); + } Ok(RetTypeOnly(y.get_type()?.into_owned())) } @@ -502,45 +481,47 @@ fn type_last_layer( let mut iter = xs.iter().enumerate(); let (_, x) = iter.next().unwrap(); for (i, y) in iter { - ensure_equal!( - x.get_type()?, - y.get_type()?, - mkerr(InvalidListElement( + if x.get_type()? != y.get_type()? { + return Err(mkerr(InvalidListElement( i, x.get_type()?.to_normalized(), - y.clone() - )) - ); + y.clone(), + ))); + } } let t = x.get_type()?; - ensure_simple_type!( - t, - TypeError::new(ctx, InvalidListType(t.to_normalized())), - ); + if t.get_type()?.as_const() != Some(Type) { + return Err(TypeError::new( + ctx, + InvalidListType(t.to_normalized()), + )); + } Ok(RetTypeOnly( Typed::from_thunk_and_type( Value::from_builtin(dhall_syntax::Builtin::List) .app(t.to_value()) .into_thunk(), - Type::from_const(dhall_syntax::Const::Type), + Typed::from_const(Type), ) .to_type(), )) } SomeLit(x) => { let t = x.get_type()?.into_owned(); - ensure_simple_type!( - t, - TypeError::new(ctx, InvalidOptionalType(t.to_normalized())), - ); + if t.get_type()?.as_const() != Some(Type) { + return Err(TypeError::new( + ctx, + InvalidOptionalType(t.to_normalized()), + )); + } Ok(RetTypeOnly( Typed::from_thunk_and_type( Value::from_builtin(dhall_syntax::Builtin::Optional) .app(t.to_value()) .into_thunk(), - Type::from_const(dhall_syntax::Const::Type), + Typed::from_const(Type).into_type(), ) .to_type(), )) @@ -625,11 +606,9 @@ fn type_last_layer( for contents in interpolated.iter() { use InterpolatedTextContents::Expr; if let Expr(x) = contents { - ensure_equal!( - x.get_type()?, - &text_type, - mkerr(InvalidTextInterpolation(x.clone())), - ); + if x.get_type()?.as_ref() != &text_type { + return Err(mkerr(InvalidTextInterpolation(x.clone()))); + } } } Ok(RetTypeOnly(text_type)) @@ -645,11 +624,9 @@ fn type_last_layer( // Check the equality of kinds. // This is to disallow expression such as: // "{ x = Text } // { y = 1 }" - ensure_equal!( - l_kind, - r_kind, - mkerr(RecordMismatch(l.clone(), r.clone())), - ); + if l_kind != r_kind { + return Err(mkerr(RecordMismatch(l.clone(), r.clone()))); + } // Extract the LHS record type let kts_x = match l_type.to_value() { @@ -729,11 +706,9 @@ fn type_last_layer( // Check the equality of kinds. // This is to disallow expression such as: // "{ x = Text } // { y = 1 }" - ensure_equal!( - l_kind, - r_kind, - mkerr(RecordMismatch(l.clone(), r.clone())), - ); + if l_kind != r_kind { + return Err(mkerr(RecordMismatch(l.clone(), r.clone()))); + } // Extract the LHS record type let kts_x = match l_type.to_value() { @@ -855,31 +830,34 @@ fn type_last_layer( _ => return Err(mkerr(BinOpTypeMismatch(*o, l.clone()))), } - ensure_equal!( - l.get_type()?, - r.get_type()?, - mkerr(BinOpTypeMismatch(*o, r.clone())) - ); + if l.get_type()? != r.get_type()? { + return Err(mkerr(BinOpTypeMismatch(*o, r.clone()))); + } Ok(RetTypeOnly(l.get_type()?.into_owned())) } BinOp(Equivalence, l, r) => { - ensure_simple_type!( - l.get_type()?, - mkerr(EquivalenceArgumentMustBeTerm(true, l.clone())), - ); - ensure_simple_type!( - r.get_type()?, - mkerr(EquivalenceArgumentMustBeTerm(false, r.clone())), - ); + if l.get_type()?.get_type()?.as_const() != Some(Type) { + return Err(mkerr(EquivalenceArgumentMustBeTerm( + true, + l.clone(), + ))); + } + if r.get_type()?.get_type()?.as_const() != Some(Type) { + return Err(mkerr(EquivalenceArgumentMustBeTerm( + false, + r.clone(), + ))); + } - ensure_equal!( - l.get_type()?, - r.get_type()?, - mkerr(EquivalenceTypeMismatch(r.clone(), l.clone())) - ); + if l.get_type()? != r.get_type()? { + return Err(mkerr(EquivalenceTypeMismatch( + r.clone(), + l.clone(), + ))); + } - Ok(RetTypeOnly(Type::from_const(dhall_syntax::Const::Type))) + Ok(RetTypeOnly(Typed::from_const(Type).into_type())) } BinOp(o, l, r) => { let t = builtin_to_type(match o { @@ -898,17 +876,13 @@ fn type_last_layer( Equivalence => unreachable!(), })?; - ensure_equal!( - l.get_type()?, - &t, - mkerr(BinOpTypeMismatch(*o, l.clone())) - ); + if l.get_type()?.as_ref() != &t { + return Err(mkerr(BinOpTypeMismatch(*o, l.clone()))); + } - ensure_equal!( - r.get_type()?, - &t, - mkerr(BinOpTypeMismatch(*o, r.clone())) - ); + if r.get_type()?.as_ref() != &t { + return Err(mkerr(BinOpTypeMismatch(*o, r.clone()))); + } Ok(RetTypeOnly(t)) } @@ -937,13 +911,13 @@ fn type_last_layer( _ => return Err(mkerr(NotAFunction(handler_type))), }; - ensure_equal!(&variant_type, &tx, { - mkerr(TypeMismatch( + if &variant_type != &tx { + return Err(mkerr(TypeMismatch( handler_type, tx.to_normalized(), variant_type, - )) - }); + ))); + } // Extract `tb` from under the `x` binder. Fails is `x` was free in `tb`. match tb.over_binder(x) { @@ -966,11 +940,9 @@ fn type_last_layer( match &inferred_type { None => inferred_type = Some(handler_return_type), Some(t) => { - ensure_equal!( - t, - &handler_return_type, - mkerr(MergeHandlerTypeMismatch) - ); + if t != &handler_return_type { + return Err(mkerr(MergeHandlerTypeMismatch)); + } } } } @@ -983,7 +955,9 @@ fn type_last_layer( match (inferred_type, type_annot) { (Some(ref t1), Some(t2)) => { let t2 = t2.to_type(); - ensure_equal!(t1, &t2, mkerr(MergeAnnotMismatch)); + if t1 != &t2 { + return Err(mkerr(MergeAnnotMismatch)); + } Ok(RetTypeOnly(t2)) } (Some(t), None) => Ok(RetTypeOnly(t)), |