Rm unsupported

crates/sml-hir-lower/src/dec.rs

@@ -360,7 +360,8 @@ fn get_spec_one(st: &mut St<'_>, dec: Option<ast::DecOne>) -> Vec<sml_hir::SpecI
         st.err(dec.syntax(), ErrorKind::Disallowed(Disallowed::Dec("`datatype`")));
       }
       if let Some(with_type) = dec.with_type() {
-        st.err(with_type.syntax(), ErrorKind::Unsupported("`withtype` in specifications"));
+        let e = ErrorKind::Disallowed(Disallowed::SuccMl("`withtype` in specifications"));
+        st.err(with_type.syntax(), e);
       }
       let binds = dat_binds(st, dec.dat_binds());
       binds.into_iter().map(|x| st.spec(sml_hir::Spec::Datatype(x), ptr.clone())).collect()

crates/sml-hir-lower/src/util.rs

@@ -43,8 +43,6 @@ impl Ptrs {
 
 #[derive(Debug)]
 pub(crate) enum ErrorKind {
-  /// must be first here, but have the highest error codes
-  Unsupported(&'static str),
   FunBindMismatchedName(String, String),
   FunBindWrongNumPats(usize, usize),
   InvalidIntLit(sml_hir::ParseIntError),
@@ -87,7 +85,6 @@ pub(crate) enum ErrorKind {
 impl fmt::Display for Error {
   fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
     match &self.kind {
-      ErrorKind::Unsupported(s) => write!(f, "unsupported: {s}"),
       ErrorKind::FunBindMismatchedName(want, got) => {
         write!(f, "expected a function clause for `{want}`, found one for `{got}`")
       }
@@ -236,7 +233,6 @@ impl Error {
   #[must_use]
   pub fn code(&self) -> Code {
     match self.kind {
-      ErrorKind::Unsupported(_) => Code::n(4999),
       ErrorKind::FunBindMismatchedName(_, _) => Code::n(4001),
       ErrorKind::FunBindWrongNumPats(_, _) => Code::n(4002),
       ErrorKind::InvalidIntLit(_) | ErrorKind::InvalidWordLit(_) => Code::n(4003),

crates/tests/src/deviations/successor_ml/withtype_spec.rs

@@ -10,7 +10,7 @@ signature STREAM =
   sig
     datatype 'a u = Nil | Cons of 'a * 'a t
     withtype 'a t = unit -> 'a u
-(** ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ unsupported: `withtype` in specifications *)
+(** ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `withtype` in specifications *)
   end
 "#,
   );

docs/diagnostics/4029.md

@@ -9,3 +9,5 @@ The language construct may have been explicitly disallowed in `millet.toml`, or
 Either allow the thing in `millet.toml`, or remove the occurrence of the thing from the code.
 
 Consult [the manual](/docs/manual.md#language) to see how to edit your `millet.toml` to allow the item.
+
+Some constructs may not be allowable because support for them in Millet is not implemented.