Add enumerate to prelude.

bryancatanzaro · May 8, 2013 · 8f76d01 · 8f76d01
1 parent 2962e59
commit 8f76d01
Show file tree

Hide file tree

Showing 3 changed files with 13 additions and 1 deletion.
diff --git a/backend b/backend
diff --git a/copperhead/prelude.py b/copperhead/prelude.py
@@ -239,7 +239,15 @@ def filter(function, sequence):
     """
     return __builtin__.filter(function, sequence)
 
+@cutype("([a]) -> [(Int, a)]")
+@_wraps(__builtin__.enumerate)
+def enumerate(x):
+    """
+    Return a sequence containing (index, value) pairs, with values
+    from the input sequence.
 
+    """
+    return list(__builtin__.enumerate(x))
 
 ############## Copperhead primitives not in Python builtins
 

diff --git a/copperhead/prelude_impl.py b/copperhead/prelude_impl.py
@@ -99,3 +99,7 @@ def rotate_el(i):
 def bounded_range(a, b):
     length = b - a
     return [xi + a for xi in range(length)]
+
+@cu
+def enumerate(x):
+    return zip(range(len(x)), x)