ch17: update from book draft

Author: ramalho

17-it-generator/aritprog_v0.py

@@ -17,7 +17,8 @@ def __init__(self, begin, step, end=None):
         self.end = end  # None -> "infinite" series
 
     def __iter__(self):
-        result = type(self.begin + self.step)(self.begin)
+        result_type = type(self.begin + self.step)
+        result = result_type(self.begin)
         forever = self.end is None
         while forever or result < self.end:
             yield result

17-it-generator/aritprog_v1.py

@@ -1,7 +1,7 @@
 """
 Arithmetic progression class
 
-# BEGIN ARITPROG_CLASS_DEMO
+# tag::ARITPROG_CLASS_DEMO[]
 
     >>> ap = ArithmeticProgression(0, 1, 3)
     >>> list(ap)
@@ -21,24 +21,25 @@
     >>> list(ap)
     [Decimal('0.0'), Decimal('0.1'), Decimal('0.2')]
 
-# END ARITPROG_CLASS_DEMO
+# end::ARITPROG_CLASS_DEMO[]
 """
 
 
-# BEGIN ARITPROG_CLASS
+# tag::ARITPROG_CLASS[]
 class ArithmeticProgression:
 
-    def __init__(self, begin, step, end=None):  # <1>
+    def __init__(self, begin, step, end=None):       # <1>
         self.begin = begin
         self.step = step
         self.end = end  # None -> "infinite" series
 
     def __iter__(self):
-        result = type(self.begin + self.step)(self.begin)  # <2>
-        forever = self.end is None  # <3>
+        result_type = type(self.begin + self.step)   # <2>
+        result = result_type(self.begin)             # <3>
+        forever = self.end is None                   # <4>
         index = 0
-        while forever or result < self.end:  # <4>
-            yield result  # <5>
+        while forever or result < self.end:          # <5>
+            yield result                             # <6>
             index += 1
-            result = self.begin + self.step * index  # <6>
-# END ARITPROG_CLASS
+            result = self.begin + self.step * index  # <7>
+# end::ARITPROG_CLASS[]

17-it-generator/aritprog_v2.py

@@ -19,7 +19,7 @@
 """
 
 
-# BEGIN ARITPROG_GENFUNC
+# tag::ARITPROG_GENFUNC[]
 def aritprog_gen(begin, step, end=None):
     result = type(begin + step)(begin)
     forever = end is None
@@ -28,4 +28,4 @@ def aritprog_gen(begin, step, end=None):
         yield result
         index += 1
         result = begin + step * index
-# END ARITPROG_GENFUNC
+# end::ARITPROG_GENFUNC[]

17-it-generator/aritprog_v3.py

@@ -1,4 +1,4 @@
-# BEGIN ARITPROG_ITERTOOLS
+# tag::ARITPROG_ITERTOOLS[]
 import itertools
 
 
@@ -8,4 +8,4 @@ def aritprog_gen(begin, step, end=None):
     if end is not None:
         ap_gen = itertools.takewhile(lambda n: n < end, ap_gen)
     return ap_gen
-# END ARITPROG_ITERTOOLS
+# end::ARITPROG_ITERTOOLS[]

17-it-generator/fibo_by_hand.py

@@ -8,7 +8,7 @@
 """
 
 
-# BEGIN FIBO_BY_HAND
+# tag::FIBO_BY_HAND[]
 class Fibonacci:
 
     def __iter__(self):
@@ -28,7 +28,7 @@ def __next__(self):
 
     def __iter__(self):
         return self
-# END FIBO_BY_HAND
+# end::FIBO_BY_HAND[]
 
 # for comparison, this is the usual implementation of a Fibonacci
 # generator in Python:

17-it-generator/isis2json/isis2json.py

@@ -200,11 +200,12 @@ def main():  # <4>
              ' for bulk insert to CouchDB via POST to db/_bulk_docs')
     parser.add_argument(
         '-m', '--mongo', action='store_true',
-        help='output individual records as separate JSON dictionaries,'
-             ' one per line for bulk insert to MongoDB via mongoimport utility')
+        help='output individual records as separate JSON dictionaries, one'
+             ' per line for bulk insert to MongoDB via mongoimport utility')
     parser.add_argument(
         '-t', '--type', type=int, metavar='ISIS_JSON_TYPE', default=1,
-        help='ISIS-JSON type, sets field structure: 1=string, 2=alist, 3=dict (default=1)')
+        help='ISIS-JSON type, sets field structure: 1=string, 2=alist,'
+             ' 3=dict (default=1)')
     parser.add_argument(
         '-q', '--qty', type=int, default=DEFAULT_QTY,
         help='maximum quantity of records to read (default=ALL)')
@@ -220,7 +221,8 @@ def main():  # <4>
         help='generate an "_id" with a random UUID for each record')
     parser.add_argument(
         '-p', '--prefix', type=str, metavar='PREFIX', default='',
-        help='concatenate prefix to every numeric field tag (ex. 99 becomes "v99")')
+        help='concatenate prefix to every numeric field tag'
+             ' (ex. 99 becomes "v99")')
     parser.add_argument(
         '-n', '--mfn', action='store_true',
         help='generate an "_id" from the MFN of each record'

17-it-generator/sentence.py

@@ -1,7 +1,18 @@
 """
 Sentence: access words by index
+
+    >>> text = 'To be, or not to be, that is the question'
+    >>> s = Sentence(text)
+    >>> len(s)
+    10
+    >>> s[1], s[5]
+    ('be', 'be')
+    >>> s
+    Sentence('To be, or no... the question')
+
 """
 
+# tag::SENTENCE_SEQ[]
 import re
 import reprlib
 
@@ -17,8 +28,10 @@ def __init__(self, text):
     def __getitem__(self, index):
         return self.words[index]  # <2>
 
-    def __len__(self, index):  # <3>
+    def __len__(self):  # <3>
         return len(self.words)
 
     def __repr__(self):
         return 'Sentence(%s)' % reprlib.repr(self.text)  # <4>
+
+# end::SENTENCE_SEQ[]

17-it-generator/sentence_gen.py

@@ -2,6 +2,7 @@
 Sentence: iterate over words using a generator function
 """
 
+# tag::SENTENCE_GEN[]
 import re
 import reprlib
 
@@ -23,3 +24,5 @@ def __iter__(self):
         return  # <3>
 
 # done! <4>
+
+# end::SENTENCE_GEN[]

17-it-generator/sentence_gen2.py

@@ -2,10 +2,11 @@
 Sentence: iterate over words using a generator function
 """
 
+# tag::SENTENCE_GEN2[]
 import re
 import reprlib
 
-RE_WORD = re.compile(r'\w+')
+RE_WORD = re.compile('r\w+')
 
 
 class Sentence:
@@ -19,3 +20,5 @@ def __repr__(self):
     def __iter__(self):
         for match in RE_WORD.finditer(self.text):  # <2>
             yield match.group()  # <3>
+
+# end::SENTENCE_GEN2[]

17-it-generator/sentence_genexp.py

@@ -2,7 +2,7 @@
 Sentence: iterate over words using a generator expression
 """
 
-# BEGIN SENTENCE_GENEXP
+# tag::SENTENCE_GENEXP[]
 import re
 import reprlib
 
@@ -19,7 +19,7 @@ def __repr__(self):
 
     def __iter__(self):
         return (match.group() for match in RE_WORD.finditer(self.text))
-# END SENTENCE_GENEXP
+# end::SENTENCE_GENEXP[]
 
 
 def main():