From dda291cfb5c39cbd337592aae46dc485363d4449 Mon Sep 17 00:00:00 2001
From: Guillermo Vaya <guillermo.vaya@gigas.com>
Date: Tue, 16 Jul 2013 14:35:57 +0200
Subject: [PATCH] make assoc accept multiple values, also added a even/odd
 check for checkargs

---
 hy/compiler.py                 | 41 +++++++++++++++++++++-------------
 tests/native_tests/language.hy |  5 +++++
 2 files changed, 31 insertions(+), 15 deletions(-)

diff --git a/hy/compiler.py b/hy/compiler.py
index 2e4e2b7..5b23272 100644
--- a/hy/compiler.py
+++ b/hy/compiler.py
@@ -318,7 +318,7 @@ def _raise_wrong_args_number(expression, error):
                                len(expression)))
 
 
-def checkargs(exact=None, min=None, max=None):
+def checkargs(exact=None, min=None, max=None, even=None):
     def _dec(fn):
         def checker(self, expression):
             if exact is not None and (len(expression) - 1) != exact:
@@ -334,6 +334,11 @@ def checkargs(exact=None, min=None, max=None):
                 _raise_wrong_args_number(
                     expression,
                     "`%%s' needs at most %d arguments, got %%d" % (max))
+                
+            is_even = not((len(expression) - 1) % 2)
+            if even is not None and is_even!=even:
+                even_str = "even" if even else "odd"
+                _raise_wrong_args_number(expression, "`%%s' needs an %s number of arguments, got %%d" % (even_str))
 
             return fn(self, expression)
 
@@ -1130,25 +1135,31 @@ class HyASTCompiler(object):
             ctx=ast.Load())
 
     @builds("assoc")
-    @checkargs(3)
+    @checkargs(min=3, even=False)
     def compile_assoc_expression(self, expr):
         expr.pop(0)  # assoc
         # (assoc foo bar baz)  => foo[bar] = baz
         target = self.compile(expr.pop(0))
-        key = self.compile(expr.pop(0))
-        val = self.compile(expr.pop(0))
+        ret = target
+        while expr != []:
+            key = self.compile(expr.pop(0))
+            try:
+                val = self.compile(expr.pop(0))
+            except IndexError:
+                raise HyCompileError("Key {key} has no value to associate".format(key))
 
-        return target + key + val + ast.Assign(
-            lineno=expr.start_line,
-            col_offset=expr.start_column,
-            targets=[
-                ast.Subscript(
-                    lineno=expr.start_line,
-                    col_offset=expr.start_column,
-                    value=target.force_expr,
-                    slice=ast.Index(value=key.force_expr),
-                    ctx=ast.Store())],
-            value=val.force_expr)
+            ret += key + val + ast.Assign(
+                lineno=expr.start_line,
+                col_offset=expr.start_column,
+                targets=[
+                    ast.Subscript(
+                        lineno=expr.start_line,
+                        col_offset=expr.start_column,
+                        value=target.force_expr,
+                        slice=ast.Index(value=key.force_expr),
+                        ctx=ast.Store())],
+                value=val.force_expr)
+        return ret
 
     @builds("with_decorator")
     @checkargs(min=1)
diff --git a/tests/native_tests/language.hy b/tests/native_tests/language.hy
index fa55e27..be2393c 100644
--- a/tests/native_tests/language.hy
+++ b/tests/native_tests/language.hy
@@ -348,6 +348,11 @@
   (assoc vals "two" "three")
   (assert (= (get vals "two") "three")))
 
+(defn test-multiassoc []
+  "NATIVE: test assoc multiple values"
+  (setv vals {"one" "two"})
+  (assoc vals "two" "three" "four" "five")
+  (assert (and (= (get vals "two") "three") (= (get vals "four") "five"))))
 
 (defn test-pass []
   "NATIVE: Test pass worksish"