Added repl and some documentation. Improved error messages. Removed dead code.

* Removed same_variant in parse::parsetree
* Added SExp::multistep (for use of the repl)

Improved error messages:
* Added parenthesis around types
* Changed how errors propagate inferring generics:
  added the error variant ArgumentsDontMatchGeneric,
  implemented the displaying of it, added tests for
  it.
* Had to change some tests to match for the new changes

1 files changed, 5 insertions, 0 deletions

diff --git a/src/type/mod.rs b/src/type/mod.rs
index aeeff93..2454f31 100644
--- a/src/type/mod.rs
+++ b/src/type/mod.rs
@@ -45,6 +45,11 @@ pub enum TypeError {
 	found:    Type,
     },
 
+    ArgumentsDontMatchGeneric {
+        argtype: Type,
+        generictype: Type,
+    },
+
     OtherError
 }