Allow calling Any as function

Fix #38.

Author: polybuildr

src/typechecker.rs

@@ -605,6 +605,11 @@ impl TypeChecker {
                     Some(func_type) => func_type,
                 }
             }
+            Type::Any => {
+                // Don't know anything about this type. Allow it to be called
+                // as func, and then assume the return type is Any.
+                return Some(Type::Any);
+            }
             v => {
                 if let Expr::Identifier(ref id) = expr.data {
                     self.issues

tests/typecheck-fail/call-any.bl

@@ -0,0 +1,8 @@
+var x = 5;
+if true {
+    x = fn () {};
+} else {
+    x = 10;
+}
+
+x();

tests/typecheck-fail/call-any.err

@@ -0,0 +1 @@
+[(MultipleTypesFromBranchWarning("x"), (11, 63))]