From 8a2ba204078b7e4f4ace398f0640e8fc1813e240 Mon Sep 17 00:00:00 2001
From: "Paul R. Tagliamonte" <paultag@debian.org>
Date: Sat, 9 Mar 2013 15:57:13 -0500
Subject: [PATCH] Adding in lambdas.

---
 hy/compiler.py                 | 22 ++++++++++++++++++++++
 tests/native_tests/language.hy |  6 ++++++
 2 files changed, 28 insertions(+)

diff --git a/hy/compiler.py b/hy/compiler.py
index 649e30f..9989ec4 100644
--- a/hy/compiler.py
+++ b/hy/compiler.py
@@ -116,6 +116,28 @@ class HyASTCompiler(object):
                           lineno=e.start_line,
                           col_offset=e.start_column)
 
+    @builds("lambda")
+    def compile_lambda_expression(self, expr):
+        expr.pop(0)
+        sig = expr.pop(0)
+        body = expr.pop(0)
+        # assert expr is empty
+        return ast.Lambda(
+            lineno=expr.start_line,
+            col_offset=expr.start_column,
+            args=ast.arguments(args=[
+                ast.Name(arg=str(x), id=str(x),
+                         ctx=ast.Param(),
+                         lineno=x.start_line,
+                         col_offset=x.start_column)
+                for x in sig],
+                vararg=None,
+                kwarg=None,
+                defaults=[],
+                kwonlyargs=[],
+                kw_defaults=[]),
+            body=self.compile(body))
+
     @builds("get")
     def compile_index_expression(self, expr):
         expr.pop(0)  # index
diff --git a/tests/native_tests/language.hy b/tests/native_tests/language.hy
index c6e84ac..7a47f47 100644
--- a/tests/native_tests/language.hy
+++ b/tests/native_tests/language.hy
@@ -63,3 +63,9 @@
   "NATIVE: Test that dict access works"
   (assert (get {"one" "two"} "one") "two")
   (assert (= (get [1 2 3 4 5] 1) 2)))
+
+
+(defn test_lambda []
+  "NATIVE: test lambda operator"
+  (def square (lambda [x] (* x x)))
+  (assert (= 4 (square 2))))