rebel-parse, rebel-lang: remove array length from types

Tuples are sufficient for fixed-length data. For arrays, the small
increase in type safety is not worth the large increase in complexity -
both for the typechecker, and the usage of the language.

The Coerce parameter of unify() is preserved for now, as it may become
useful again for other types like sets.

2 files changed, 3 insertions, 21 deletions

diff --git a/crates/rebel-parse/src/ast/typ.rs b/crates/rebel-parse/src/ast/typ.rs
index 18ea827..939b67d 100644
--- a/crates/rebel-parse/src/ast/typ.rs
+++ b/crates/rebel-parse/src/ast/typ.rs
@@ -11,17 +11,10 @@ pub enum Type<'a> {
 pub enum Literal<'a> {
 	Unit,
 	Tuple(Vec<Type<'a>>),
-	Array(Box<Type<'a>>, ArrayLen),
+	Array(Box<Type<'a>>),
 	Struct(Vec<StructField<'a>>),
 }
 
-#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
-pub enum ArrayLen {
-	Free,
-	Fixed(u32),
-	Dynamic,
-}
-
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub struct StructField<'a> {
 	pub name: &'a str,
diff --git a/crates/rebel-parse/src/grammar/recipe.rs b/crates/rebel-parse/src/grammar/recipe.rs
index c9fe1e2..b1ac32f 100644
--- a/crates/rebel-parse/src/grammar/recipe.rs
+++ b/crates/rebel-parse/src/grammar/recipe.rs
@@ -72,24 +72,13 @@ peg::parser! {
 			/ p('(') elements:(typ() ** p(',')) p(',')? p(')') {
 				typ::Literal::Tuple(elements)
 			}
-			/ p('[') typ:typ() len:array_len() p(']') {
-				typ::Literal::Array(Box::new(typ), len)
+			/ p('[') typ:typ() p(']') {
+				typ::Literal::Array(Box::new(typ))
 			}
 			/ p('{') entries:delimited(<struct_field_typ()>, <p(',')>) p('}') {
 				typ::Literal::Struct(entries)
 			}
 
-		rule array_len() -> typ::ArrayLen
-			= p(';') len:number() { ?
-				Ok(typ::ArrayLen::Fixed(len.try_into().or(Err("Invalid array length"))?))
-			}
-			/ p(';') [Token::Ident(name) if *name == "_"] {
-				typ::ArrayLen::Free
-			}
-			/ {
-				typ::ArrayLen::Dynamic
-			}
-
 		rule pat() -> Pat<'a>
 			= path:path() { Pat::Path(path) }