diff options
Diffstat (limited to 'src/cmd/compile/internal/types2/typeterm.go')
| -rw-r--r-- | src/cmd/compile/internal/types2/typeterm.go | 31 |
1 files changed, 14 insertions, 17 deletions
diff --git a/src/cmd/compile/internal/types2/typeterm.go b/src/cmd/compile/internal/types2/typeterm.go index 59a89cb004..8edbefa579 100644 --- a/src/cmd/compile/internal/types2/typeterm.go +++ b/src/cmd/compile/internal/types2/typeterm.go @@ -4,13 +4,10 @@ package types2 -// TODO(gri) use a different symbol instead of ⊤ for the set of all types -// (⊤ is hard to distinguish from T in some fonts) - // A term describes elementary type sets: // // ∅: (*term)(nil) == ∅ // set of no types (empty set) -// ⊤: &term{} == ⊤ // set of all types +// 𝓤: &term{} == 𝓤 // set of all types (𝓤niverse) // T: &term{false, T} == {T} // set of type T // ~t: &term{true, t} == {t' | under(t') == t} // set of types with underlying type t // @@ -24,7 +21,7 @@ func (x *term) String() string { case x == nil: return "∅" case x.typ == nil: - return "⊤" + return "𝓤" case x.tilde: return "~" + x.typ.String() default: @@ -41,7 +38,7 @@ func (x *term) equal(y *term) bool { case x.typ == nil || y.typ == nil: return x.typ == y.typ } - // ∅ ⊂ x, y ⊂ ⊤ + // ∅ ⊂ x, y ⊂ 𝓤 return x.tilde == y.tilde && Identical(x.typ, y.typ) } @@ -57,11 +54,11 @@ func (x *term) union(y *term) (_, _ *term) { case y == nil: return x, nil // x ∪ ∅ == x case x.typ == nil: - return x, nil // ⊤ ∪ y == ⊤ + return x, nil // 𝓤 ∪ y == 𝓤 case y.typ == nil: - return y, nil // x ∪ ⊤ == ⊤ + return y, nil // x ∪ 𝓤 == 𝓤 } - // ∅ ⊂ x, y ⊂ ⊤ + // ∅ ⊂ x, y ⊂ 𝓤 if x.disjoint(y) { return x, y // x ∪ y == (x, y) if x ∩ y == ∅ @@ -85,11 +82,11 @@ func (x *term) intersect(y *term) *term { case x == nil || y == nil: return nil // ∅ ∩ y == ∅ and ∩ ∅ == ∅ case x.typ == nil: - return y // ⊤ ∩ y == y + return y // 𝓤 ∩ y == y case y.typ == nil: - return x // x ∩ ⊤ == x + return x // x ∩ 𝓤 == x } - // ∅ ⊂ x, y ⊂ ⊤ + // ∅ ⊂ x, y ⊂ 𝓤 if x.disjoint(y) { return nil // x ∩ y == ∅ if x ∩ y == ∅ @@ -113,9 +110,9 @@ func (x *term) includes(t Type) bool { case x == nil: return false // t ∈ ∅ == false case x.typ == nil: - return true // t ∈ ⊤ == true + return true // t ∈ 𝓤 == true } - // ∅ ⊂ x ⊂ ⊤ + // ∅ ⊂ x ⊂ 𝓤 u := t if x.tilde { @@ -133,11 +130,11 @@ func (x *term) subsetOf(y *term) bool { case y == nil: return false // x ⊆ ∅ == false since x != ∅ case y.typ == nil: - return true // x ⊆ ⊤ == true + return true // x ⊆ 𝓤 == true case x.typ == nil: - return false // ⊤ ⊆ y == false since y != ⊤ + return false // 𝓤 ⊆ y == false since y != 𝓤 } - // ∅ ⊂ x, y ⊂ ⊤ + // ∅ ⊂ x, y ⊂ 𝓤 if x.disjoint(y) { return false // x ⊆ y == false if x ∩ y == ∅ |