From 73be6afd3a25a4e2d91a70294e9d310971cc9ff5 Mon Sep 17 00:00:00 2001
From: "Paul R. Tagliamonte" <paultag@debian.org>
Date: Tue, 9 Apr 2013 21:33:09 -0400
Subject: [PATCH] Initial cut of `eval'

---
 hy/compiler.py | 18 ++++++++++++++++--
 hy/importer.py | 15 ++++++++++++++-
 2 files changed, 30 insertions(+), 3 deletions(-)

diff --git a/hy/compiler.py b/hy/compiler.py
index 0157142..3901c8b 100644
--- a/hy/compiler.py
+++ b/hy/compiler.py
@@ -133,7 +133,8 @@ class HyASTCompiler(object):
                                  start_line=getattr(e, "start_line", 0),
                                  start_column=getattr(e, "start_column", 0))
 
-        raise HyCompileError("Unknown type - `%s'" % (str(type(tree))))
+        raise HyCompileError(
+            "Unknown type - `%s' - %s" % (str(type(tree)), tree))
 
     def _mangle_branch(self, tree, start_line, start_column):
         # If tree is empty, just return a pass statement
@@ -191,6 +192,14 @@ class HyASTCompiler(object):
     def compile_quote(self, entries):
         return self.compile(self._render_quoted_form(entries[1]))
 
+    @builds("eval")
+    @checkargs(exact=1)
+    def compile_eval(self, expr):
+        expr.pop(0)
+        return self.compile(HyExpression([
+            HySymbol("hy_eval")] + expr + [HyExpression([HySymbol("globals")])
+        ]).replace(expr))
+
     @builds("do")
     @builds("progn")
     def compile_do_expression(self, expr):
@@ -925,5 +934,10 @@ def hy_compile(tree, root=None):
     tlo = root
     if root is None:
         tlo = ast.Module
-    ret = tlo(body=compiler._mangle_branch(compiler.compile(tree), 0, 0))
+
+    _ast = compiler.compile(tree)
+    if type(_ast) == list:
+        _ast = compiler._mangle_branch(_ast, 0, 0)
+
+    ret = tlo(body=_ast)
     return ret
diff --git a/hy/importer.py b/hy/importer.py
index 587d536..94ed984 100644
--- a/hy/importer.py
+++ b/hy/importer.py
@@ -18,8 +18,9 @@
 # FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 # DEALINGS IN THE SOFTWARE.
 
-from hy.compiler import hy_compile
 from py_compile import wr_long, MAGIC
+from hy.compiler import hy_compile
+from hy.models import HyObject
 from hy.core import process
 from hy.lex import tokenize
 
@@ -28,6 +29,7 @@ from io import open
 import marshal
 import imp
 import sys
+import ast
 import os
 
 
@@ -67,6 +69,17 @@ def import_file_to_module(name, fpath):
     return mod
 
 
+def hy_eval(hytree, namespace):
+    foo = HyObject()
+    foo.start_line = 0
+    foo.end_line = 0
+    foo.start_column = 0
+    foo.end_column = 0
+    hytree.replace(foo)
+    _ast = hy_compile(hytree, root=ast.Expression)
+    return eval(compile(_ast, "<eval>", "eval"), namespace)
+
+
 def write_hy_as_pyc(fname):
     with open(fname, 'U') as f:
         try: