Improve three recipes in the itertools docs.
diff --git a/Doc/lib/libitertools.tex b/Doc/lib/libitertools.tex
index df73561..be53015 100644
--- a/Doc/lib/libitertools.tex
+++ b/Doc/lib/libitertools.tex
@@ -458,15 +458,21 @@
 
 def all(seq, pred=bool):
     "Returns True if pred(x) is True for every element in the iterable"
-    return False not in imap(pred, seq)
+    for elem in ifilterfalse(pred, seq):
+        return False
+    return True
 
 def any(seq, pred=bool):
-    "Returns True if pred(x) is True at least one element in the iterable"
-    return True in imap(pred, seq)
+    "Returns True if pred(x) is True for at least one element in the iterable"
+    for elem in ifilter(pred, seq):
+        return True
+    return False
 
 def no(seq, pred=bool):
     "Returns True if pred(x) is False for every element in the iterable"
-    return True not in imap(pred, seq)
+    for elem in ifilter(pred, seq):
+        return False
+    return True
 
 def quantify(seq, pred=bool):
     "Count how many times the predicate is True in the sequence"