Got &rest working, tests pass

Did a little house cleaning in lex states.py too and started removing
stupid print() statements.

hy/compiler.py

@@ -175,11 +175,11 @@ class HyASTCompiler(object):
         return ret
 
     def _parse_lambda_list(self, exprs):
-        """ Return args, keywords, starargs, kwargs from exprs."""
+        """ Return args, keywords, varargs, kwargs from exprs."""
         exprs.reverse()
         args = []
         keywords = []
-        starargs = None
+        varargs = None
         kwargs = {}
         lambda_keyword = None
 
@@ -191,7 +191,6 @@ class HyASTCompiler(object):
                     raise HyCompileError("{0} is not a valid "
                                          "lambda-keyword.".format(repr(expr)))
                 if expr == "&rest" and lambda_keyword is None:
-                    print("Found &rest")
                     lambda_keyword = expr
                 elif expr == "&optional" and lambda_keyword == "&rest":
                     lambda_keyword = expr
@@ -207,11 +206,10 @@ class HyASTCompiler(object):
             if lambda_keyword is None:
                 args.append(expr)
             elif lambda_keyword == "&rest":
-                print("The keyword is &rest, the expr is {0}".format(expr))
-                if starargs:
+                if varargs:
                     raise HyCompileError("There can only be one "
                                          "&rest argument")
-                starargs = str(expr)
+                varargs = str(expr)
             elif lambda_keyword == "&optional":
                 # add key to keywords and kwargs, value to kwargs? Look up AST docs you dummy.
                 pass
@@ -221,7 +219,7 @@ class HyASTCompiler(object):
 
         if not kwargs:
             kwargs = None
-        return args, keywords, starargs, kwargs
+        return args, keywords, varargs, kwargs
 
     @builds(list)
     def compile_raw_list(self, entries):

hy/lex/states.py

@@ -167,7 +167,7 @@ class ListeyThing(State):
             return Idle
 
         if char in ")]}":
-            raise LexException("Unexpected closing character: `%s'" % (char))
+            raise LexException("Unexpected closing character: `{0}'".format(char))
 
         if char in WHITESPACE:
             self.commit()
@@ -248,7 +248,7 @@ class String(State):
                 self.nodes.append("\"")
                 return
 
-            raise LexException("Unknown modifier: `%s'" % (char))
+            raise LexException("Unknown modifier: `{0}'".format(char))
 
         if char == "\"":
             return Idle
@@ -292,7 +292,7 @@ class Idle(State):
         if char in WHITESPACE:
             return
 
-        raise LexException("Unknown char (Idle state): `%s`" % (char))
+        raise LexException("Unknown char (Idle state): `{0}`".format(char))
 
 
 class Comment(State):
@@ -327,4 +327,4 @@ class Hash(State):
         if char == "!":
             return Comment
 
-        raise LexException("Unknown char (Hash state): `%s`" % (char))
+        raise LexException("Unknown char (Hash state): `{0}'".format(char))

tests/compilers/test_ast.py

@@ -328,9 +328,7 @@ def test_ast_tuple():
     assert type(code) == ast.Tuple
 
 
-def test_lambda_list_keywords_rest():
-    src = ("(defun foo (x &rest xs) (print xs))\n"
-           "(foo 1 2 3 4 5)")
-    code = hy_compile(tokenize(src))
-    print(dump(code))
-    assert False
+def test_lambda_list_keywords():
+    """ Ensure we can compile functions with lambda list keywords."""
+    hy_compile(tokenize("(fn (x &rest xs) (print xs))"))
+    cant_compile("(fn (x &rest xs &rest ys) (print xs))")