port headers!

compiler/parse/src/module.rs

@@ -8,7 +8,7 @@ use crate::header::{
 use crate::ident::{lowercase_ident, unqualified_ident, uppercase_ident};
 use crate::parser::Progress::{self, *};
 use crate::parser::{
-    backtrackable, end_of_file, loc, specialize, word1, Col, EEffects, EExposes, EHeader, EImports,
+    backtrackable, end_of_file, specialize, word1, Col, EEffects, EExposes, EHeader, EImports,
     EPackages, EProvides, ERequires, ETypedIdent, Parser, Row, State, SyntaxError,
 };
 use crate::string_literal;
@@ -95,6 +95,10 @@ fn chomp_module_name<'a>(buffer: &'a [u8]) -> Result<&'a str, Progress> {
             if let Ok((first_letter, width)) = char::from_utf8_slice_start(&buffer[chomped..]) {
                 if first_letter.is_uppercase() {
                     chomped += width;
+                } else if first_letter == '{' {
+                    // the .{ starting a `Foo.{ bar, baz }` importing clauses
+                    chomped -= width;
+                    break;
                 } else {
                     return Err(Progress::MadeProgress);
                 }
@@ -246,7 +250,7 @@ fn platform_header<'a>() -> impl Parser<'a, PlatformHeader<'a>, EHeader<'a>> {
 #[inline(always)]
 pub fn module_defs<'a>() -> impl Parser<'a, Vec<'a, Located<Def<'a>>>, SyntaxError<'a>> {
     // force that we pare until the end of the input
-    skip_second!(zero_or_more!(space0_around(loc(def(0)), 0)), end_of_file())
+    skip_second!(zero_or_more!(space0_around(loc!(def(0)), 0)), end_of_file())
 }
 #[derive(Debug)]
 struct ProvidesTo<'a> {

compiler/reporting/src/error/parse.rs

@@ -2800,6 +2800,29 @@ fn to_imports_report<'a>(
 
         EImports::Space(error, row, col) => to_space_report(alloc, filename, &error, row, col),
 
+        EImports::ModuleName(row, col) => {
+            let surroundings = Region::from_rows_cols(start_row, start_col, row, col);
+            let region = Region::from_row_col(row, col);
+
+            let doc = alloc.stack(vec![
+                alloc.reflow(r"I am partway through parsing a header, but got stuck here:"),
+                alloc.region_with_subregion(surroundings, region),
+                alloc.concat(vec![
+                    alloc.reflow("I am expecting a module name next, like "),
+                    alloc.parser_suggestion("BigNum"),
+                    alloc.reflow(" or "),
+                    alloc.parser_suggestion("Main"),
+                    alloc.reflow(". Module names must start with an uppercase letter."),
+                ]),
+            ]);
+
+            Report {
+                filename,
+                doc,
+                title: "WEIRD MODULE NAME".to_string(),
+            }
+        }
+
         _ => todo!("unhandled parse error {:?}", parse_problem),
     }
 }