From 504c1db541d0884aad21537e9fc62fd8bba56c39 Mon Sep 17 00:00:00 2001
From: Roman Zeyde <roman.zeyde@gmail.com>
Date: Sun, 21 Sep 2014 17:16:30 +0300
Subject: [PATCH] common: iterate() should not enumerate on default

---
 amodem/common.py     | 4 ++--
 amodem/framing.py    | 8 ++++----
 amodem/recv.py       | 6 +++---
 amodem/send.py       | 3 ++-
 tests/test_common.py | 5 ++++-
 5 files changed, 15 insertions(+), 11 deletions(-)

diff --git a/amodem/common.py b/amodem/common.py
index ab9acf9..47b0484 100644
--- a/amodem/common.py
+++ b/amodem/common.py
@@ -36,7 +36,7 @@ def dumps(sym, n=1):
     return data * n
 
 
-def iterate(data, size, func=None, truncate=True):
+def iterate(data, size, func=None, truncate=True, enumerate=False):
     offset = 0
     data = iter(data)
 
@@ -49,7 +49,7 @@ def iterate(data, size, func=None, truncate=True):
             done = True
 
         result = func(buf) if func else np.array(buf)
-        yield offset, result
+        yield (offset, result) if enumerate else result
         offset += size
 
 
diff --git a/amodem/framing.py b/amodem/framing.py
index d501351..2a0b7e6 100644
--- a/amodem/framing.py
+++ b/amodem/framing.py
@@ -45,8 +45,8 @@ class Framer(object):
         return struct.pack(self.prefix_fmt, len(frame)) + frame
 
     def encode(self, data):
-        for _, block in common.iterate(data=data, size=self.block_size,
-                                       func=bytearray, truncate=False):
+        for block in common.iterate(data=data, size=self.block_size,
+                                    func=bytearray, truncate=False):
             yield self._pack(block=block)
         yield self._pack(block=self.EOF)
 
@@ -95,8 +95,8 @@ def encode(data, framer=None):
 
 @chain_wrapper
 def _to_bytes(bits, block_size=1):
-    for _, chunk in common.iterate(data=bits, size=8*block_size,
-                                   func=lambda x: x, truncate=True):
+    for chunk in common.iterate(data=bits, size=8*block_size,
+                                func=lambda x: x, truncate=True):
         yield bitarray.bitarray(chunk, endian='little').tobytes()
 
 
diff --git a/amodem/recv.py b/amodem/recv.py
index eb47f01..46e74d7 100644
--- a/amodem/recv.py
+++ b/amodem/recv.py
@@ -44,7 +44,7 @@ def report_carrier(bufs, begin):
 def detect(samples, freq):
     counter = 0
     bufs = collections.deque([], maxlen=config.baud)  # 1 second of symbols
-    for offset, buf in common.iterate(samples, config.Nsym):
+    for offset, buf in common.iterate(samples, config.Nsym, enumerate=True):
         bufs.append(buf)
 
         coeff = dsp.coherence(buf, config.Fc)
@@ -230,8 +230,8 @@ class Receiver(object):
     def run(self, output):
         data = framing.decode(self.bitstream)
         self.size = 0
-        for _, chunk in common.iterate(data=data, size=256,
-                                       truncate=False, func=bytearray):
+        for chunk in common.iterate(data=data, size=256,
+                                    truncate=False, func=bytearray):
             output.write(chunk)
             self.size += len(chunk)
 
diff --git a/amodem/send.py b/amodem/send.py
index 56f52de..0caaa3e 100644
--- a/amodem/send.py
+++ b/amodem/send.py
@@ -45,7 +45,8 @@ class Writer(object):
         bits = itertools.chain(bits, padding)
         symbols_iter = modem.qam.encode(bits)
         carriers = modem.carriers / config.Nfreq
-        for i, symbols in common.iterate(symbols_iter, size=config.Nfreq):
+        for i, symbols in common.iterate(symbols_iter,
+                                         size=config.Nfreq, enumerate=True):
             symbols = np.array(list(symbols))
             self.write(np.dot(symbols, carriers))
 
diff --git a/tests/test_common.py b/tests/test_common.py
index 8684692..fe174a2 100644
--- a/tests/test_common.py
+++ b/tests/test_common.py
@@ -4,7 +4,10 @@ import numpy as np
 
 def iterlist(x, *args, **kwargs):
     x = np.array(x)
-    return list((i, list(x)) for i, x in common.iterate(x, *args, **kwargs))
+    return list(
+        (i, list(x))
+        for i, x in common.iterate(x, enumerate=True, *args, **kwargs)
+    )
 
 
 def test_iterate():