py3k: map and filter to list comprehensions

What's really going on is that map() and filter() return iterators in py3k.
I've just gone ahead and turned them all into list comprehensions, because
I find them much easier to read.

PIL/BdfFontFile.py

@@ -69,8 +69,8 @@ def bdf_char(f):
         bitmap.append(s[:-1])
     bitmap = "".join(bitmap)
 
-    [x, y, l, d] = map(int, props["BBX"].split())
-    [dx, dy] = map(int, props["DWIDTH"].split())
+    [x, y, l, d] = [int(s) for s in props["BBX"].split()]
+    [dx, dy] = [int(s) for s in props["DWIDTH"].split()]
 
     bbox = (dx, dy), (l, -d-y, x+l, -d), (0, 0, x, y)
 

PIL/EpsImagePlugin.py

@@ -183,7 +183,7 @@ class EpsImageFile(ImageFile.ImageFile):
                         # Note: The DSC spec says that BoundingBox
                         # fields should be integers, but some drivers
                         # put floating point values there anyway.
-                        box = map(int, map(float, v.split()))
+                        box = [int(float(s)) for s in v.split()]
                         self.size = box[2] - box[0], box[3] - box[1]
                         self.tile = [("eps", (0,0) + self.size, offset,
                                       (length, box))]

PIL/FliImagePlugin.py

@@ -63,7 +63,7 @@ class FliImageFile(ImageFile.ImageFile):
         self.info["duration"] = duration
 
         # look for palette
-        palette = map(lambda a: (a,a,a), range(256))
+        palette = [(a,a,a) for a in range(256)]
 
         s = self.fp.read(16)
 
@@ -82,7 +82,7 @@ class FliImageFile(ImageFile.ImageFile):
             elif i16(s[4:6]) == 4:
                 self._palette(palette, 0)
 
-        palette = map(lambda (r,g,b): chr(r)+chr(g)+chr(b), palette)
+        palette = [chr(r)+chr(g)+chr(b) for (r,g,b) in palette]
         self.palette = ImagePalette.raw("RGB", "".join(palette))
 
         # set things up to decode first frame

PIL/GimpGradientFile.py

@@ -105,7 +105,7 @@ class GimpGradientFile(GradientFile):
         for i in range(count):
 
             s = fp.readline().split()
-            w = map(float, s[:11])
+            w = [float(x) for x in s[:11]]
 
             x0, x1  = w[0], w[2]
             xm      = w[1]

PIL/GimpPaletteFile.py

@@ -25,7 +25,7 @@ class GimpPaletteFile:
 
     def __init__(self, fp):
 
-        self.palette = map(lambda i: chr(i)*3, range(256))
+        self.palette = [chr(i)*3 for i in range(256)]
 
         if fp.readline()[:12] != "GIMP Palette":
             raise SyntaxError("not a GIMP palette file")

PIL/ImImagePlugin.py

@@ -209,7 +209,7 @@ class ImImageFile(ImageFile.ImageFile):
             if self.mode == "L" or self.mode == "LA":
                 if greyscale:
                     if not linear:
-                        self.lut = map(ord, palette[:256])
+                        self.lut = [ord(c) for c in palette[:256]]
                 else:
                     if self.mode == "L":
                         self.mode = self.rawmode = "P"
@@ -218,7 +218,7 @@ class ImImageFile(ImageFile.ImageFile):
                     self.palette = ImagePalette.raw("RGB;L", palette)
             elif self.mode == "RGB":
                 if not greyscale or not linear:
-                    self.lut = map(ord, palette)
+                    self.lut = [ord(c) for c in palette]
 
         self.frame = 0
 

PIL/Image.py

@@ -930,7 +930,7 @@ class Image:
 
         self.load()
         try:
-            return map(ord, self.im.getpalette())
+            return [ord(c) for c in self.im.getpalette()]
         except ValueError:
             return None # no palette
 
@@ -959,7 +959,7 @@ class Image:
 
         self.load()
         x, y = self.im.getprojection()
-        return map(ord, x), map(ord, y)
+        return [ord(c) for c in x], [ord(c) for c in y]
 
     ##
     # Returns a histogram for the image. The histogram is returned as
@@ -1129,7 +1129,7 @@ class Image:
                 scale, offset = _getscaleoffset(lut)
                 return self._new(self.im.point_transform(scale, offset))
             # for other modes, convert the function to a table
-            lut = map(lut, range(256)) * self.im.bands
+            lut = [lut(i) for i in range(256)] * self.im.bands
 
         if self.mode == "F":
             # FIXME: _imaging returns a confusing error message for this case

PIL/ImageOps.py

@@ -209,7 +209,7 @@ def equalize(image, mask=None):
     h = image.histogram(mask)
     lut = []
     for b in range(0, len(h), 256):
-        histo = filter(None, h[b:b+256])
+        histo = [_f for _f in h[b:b+256] if _f]
         if len(histo) <= 1:
             lut.extend(range(256))
         else:

PIL/ImagePalette.py

@@ -59,7 +59,7 @@ class ImagePalette:
             except KeyError:
                 # allocate new color slot
                 if Image.isStringType(self.palette):
-                    self.palette = map(int, self.palette)
+                    self.palette = [int(x) for x in self.palette]
                 index = len(self.colors)
                 if index >= 256:
                     raise ValueError("cannot allocate more than 256 colors")

PIL/OleFileIO.py

@@ -307,7 +307,7 @@ class OleFileIO:
             if ix == -2 or ix == -1: # ix == 0xFFFFFFFEL or ix == 0xFFFFFFFFL:
                 break
             s = self.getsect(ix)
-            fat = fat + map(lambda i, s=s: i32(s, i), range(0, len(s), 4))
+            fat = fat + [i32(s, i) for i in range(0, len(s), 4)]
         self.fat = fat
 
     def loadminifat(self):
@@ -316,7 +316,7 @@ class OleFileIO:
 
         s = self._open(self.minifatsect).read()
 
-        self.minifat = map(lambda i, s=s: i32(s, i), range(0, len(s), 4))
+        self.minifat = [i32(s, i) for i in range(0, len(s), 4)]
 
     def getsect(self, sect):
         # Read given sector

PIL/PaletteFile.py

@@ -22,7 +22,7 @@ class PaletteFile:
 
     def __init__(self, fp):
 
-        self.palette = map(lambda i: (i, i, i), range(256))
+        self.palette = [(i, i, i) for i in range(256)]
 
         while 1:
 
@@ -35,7 +35,7 @@ class PaletteFile:
             if len(s) > 100:
                 raise SyntaxError("bad palette file")
 
-            v = map(int, s.split())
+            v = [int(x) for x in s.split()]
             try:
                 [i, r, g, b] = v
             except ValueError:

PIL/TiffImagePlugin.py

@@ -701,7 +701,7 @@ class TiffImageFile(ImageFile.ImageFile):
         # fixup palette descriptor
 
         if self.mode == "P":
-            palette = map(lambda a: chr(a / 256), self.tag[COLORMAP])
+            palette = [chr(a / 256) for a in self.tag[COLORMAP]]
             self.palette = ImagePalette.raw("RGB;L", "".join(palette))
 #
 # --------------------------------------------------------------------
@@ -823,7 +823,7 @@ def _save(im, fp, filename):
 
     if im.mode == "P":
         lut = im.im.getpalette("RGB", "RGB;L")
-        ifd[COLORMAP] = tuple(map(lambda v: ord(v) * 256, lut))
+        ifd[COLORMAP] = tuple(ord(v) * 256 for v in lut)
 
     # data orientation
     stride = len(bits) * ((im.size[0]*bits[0]+7)/8)