refactor: change conversions to use a stricter function with deduplicated code

1 files changed, 13 insertions, 4 deletions

diff --git a/src/type/check.rs b/src/type/check.rs
index a54ffc2..f1c4a2b 100644
--- a/src/type/check.rs
+++ b/src/type/check.rs
@@ -330,7 +330,9 @@ impl SExp {
 			}
 			match &ty {
 			    None => ty = Some(arm.infer_type(newctx)?),
-			    Some(t) => ty = Some(t.least_general_supertype(&arm.infer_type(newctx.clone())?)),
+			    Some(t) => if arm.infer_type(newctx)? != *t {
+				return Err(OtherError);
+			    },
 			}
 		    }
 		    if !has_wildcard {
@@ -346,8 +348,15 @@ impl SExp {
                 let opertype = (*op).infer_type(ctx.clone())?;
                 let argstype =  (*l).infer_list_type(ctx)?;
 
+		// makes [x] x
+		let argstype = match argstype {
+		    List(v) if v.get(0).is_some() && v.get(1).is_none() => 
+			v.get(0).unwrap().clone(),
+		    t => t,
+		};
+
 		let conv_args = match (opertype.clone(), argstype.clone()) {
-		    (Arrow(from, _), a) => match a.clone().into_type(&*from) {
+		    (Arrow(from, _), a) => match a.clone().convert(&*from) {
 			Ok(s) => Ok(s),
 			Err(()) => Err(InvalidArgList {
 			    arglist: (**l).clone(),
@@ -370,9 +379,9 @@ impl SExp {
                     opertype.infer_generics(&conv_args)?
                 };
 
-                match (opertype, argstype) {
+                match (opertype, conv_args) {
                     (Arrow(a, b), c) => {
-                        if c.aka(&*a) {
+                        if c == *a {
 			    Ok(*b)
 			} else {
                             Err(InvalidArgList {