diff --git a/README.md b/README.md index aa2a877..10e7f96 100644 --- a/README.md +++ b/README.md @@ -1172,8 +1172,8 @@ Iterable Duck Types ------------------- ### Iterable -* **Only required method for iterable is iter(), that should return an iterator of its contents.** -* **Contains() is automatically generated whenever iter() is present.** +* **Only required method for iterable is iter(). It should return an iterator of its contents.** +* **Contains() automatically works on any object that has iter() defined.** ```python class MyIterable: def __init__(self, a): @@ -1192,58 +1192,69 @@ True ``` ### Collection -* **Every collection is also an iterable.** +* **Only required methods are iter() and len().** * **This cheatsheet actually means `''` when it uses `''`.** * **I chose not to use the name iterable because it sounds scarier and more vague than collection.** ```python class MyCollection: def __init__(self, a): self.a = a + def __iter__(self): + for el in self.a: + yield el def __contains__(self, el): return el in self.a def __len__(self): return len(self.a) - def __iter__(self): - for el in self.a: - yield el ``` ### Sequence -* **Every sequence is also a collection.** -* **Iter() and reversed() are automatically generated whenever getitem() is present.** +* **Only required methods are len() and getitem().** +* **Iter(), contains() and reversed() automatically work on any object that has getitem() defined.** ```python class MySequence: def __init__(self, a): self.a = a - def __getitem__(self, i): - return self.a[i] + def __iter__(self): + for el in self.a: + yield el + def __contains__(self, el): + return el in self.a def __len__(self): return len(self.a) + def __getitem__(self, i): + return self.a[i] + def __reversed__(self): + return reversed(self.a) ``` ### Collections.abc.Sequence * **It's a richer interface than the basic sequence.** -* **Extending it generates contains(), iter(), reversed(), index(), and count().** +* **Extending it generates iter(), contains(), reversed(), index(), and count().** * **Unlike `'abc.Iterable'` and `'abc.Collection'`, it is not a duck type. That's why `'issubclass(MySequence, collections.abc.Sequence)'` would return 'False' even if it had all the methods defined.** ```python class MyAbcSequence(collections.abc.Sequence): def __init__(self, a): self.a = a - def __getitem__(self, i): - return self.a[i] def __len__(self): return len(self.a) + def __getitem__(self, i): + return self.a[i] ``` -#### Table of the methods that each (duck) type provides: +#### Table of the required and available methods: ```text +------------+----------+------------+----------+--------------+ | | Iterable | Collection | Sequence | abc.Sequence | +------------+----------+------------+----------+--------------+ -| iter() | yes | yes | yes | yes | -| len() | | yes | yes | yes | -| getitem() | | | yes | yes | -| contains() | | yes | | yes | +| iter() | REQ | REQ | yes | yes | +| contains() | yes | yes | yes | yes | +| len() | | REQ | REQ | REQ | +| getitem() | | | REQ | REQ | +| reversed() | | | yes | yes | +| reverse() | | | | yes | +| index() | | | | yes | +| count() | | | | yes | +------------+----------+------------+----------+--------------+ ``` diff --git a/index.html b/index.html index ed776a2..220de28 100644 --- a/index.html +++ b/index.html @@ -1087,8 +1087,8 @@ con = sqlite3.connect('<path>'); #Iterable Duck Types

Iterable

    -
  • Only required method for iterable is iter(), that should return an iterator of its contents.
    • -
  • Contains() is automatically generated whenever iter() is present.
    • +
  • Only required method for iterable is iter(). It should return an iterator of its contents.
    • +
  • Contains() automatically works on any object that has iter() defined.
class MyIterable:
     def __init__(self, a):
@@ -1105,56 +1105,67 @@ con  = sqlite3.connect('<path>');

Collection

    -
  • Every collection is also an iterable.
    • +
  • Only required methods are iter() and len().
  • This cheatsheet actually means '<iterable>' when it uses '<collection>'.
  • I chose not to use the name iterable because it sounds scarier and more vague than collection.
class MyCollection:
     def __init__(self, a):
         self.a = a
+    def __iter__(self):
+        for el in self.a:
+            yield el
     def __contains__(self, el):
         return el in self.a
     def __len__(self):
         return len(self.a)
-    def __iter__(self):
-        for el in self.a:
-            yield el

Sequence

    -
  • Every sequence is also a collection.
    • -
  • Iter() and reversed() are automatically generated whenever getitem() is present.
    • +
  • Only required methods are len() and getitem().
    • +
  • Iter(), contains() and reversed() automatically work on any object that has getitem() defined.
class MySequence:
     def __init__(self, a):
         self.a = a
-    def __getitem__(self, i):
-        return self.a[i]
+    def __iter__(self):
+        for el in self.a:
+            yield el
+    def __contains__(self, el):
+        return el in self.a
     def __len__(self):
         return len(self.a)
+    def __getitem__(self, i):
+        return self.a[i]
+    def __reversed__(self):
+        return reversed(self.a)

Collections.abc.Sequence

  • It's a richer interface than the basic sequence.
    • -
  • Extending it generates contains(), iter(), reversed(), index(), and count().
    • +
  • Extending it generates iter(), contains(), reversed(), index(), and count().
  • Unlike 'abc.Iterable' and 'abc.Collection', it is not a duck type. That's why 'issubclass(MySequence, collections.abc.Sequence)' would return 'False' even if it had all the methods defined.
class MyAbcSequence(collections.abc.Sequence):
     def __init__(self, a):
         self.a = a
-    def __getitem__(self, i):
-        return self.a[i]
     def __len__(self):
         return len(self.a)
+    def __getitem__(self, i):
+        return self.a[i]
-

Table of the methods that each (duck) type provides:

+

Table of the required and available methods:

┏━━━━━━━━━━━━┯━━━━━━━━━━┯━━━━━━━━━━━━┯━━━━━━━━━━┯━━━━━━━━━━━━━━┓
 ┃            │ Iterable │ Collection │ Sequence │ abc.Sequence ┃
 ┠────────────┼──────────┼────────────┼──────────┼──────────────┨
-┃ iter()     │    ✓     │     ✓      │    ✓     │      ✓       ┃
-┃ len()      │          │     ✓      │    ✓     │      ✓       ┃
-┃ getitem()  │          │     +      │    ✓     │      ✓       ┃
-┃ contains() │          │     ✓      │          │      ✓       ┃
+┃ iter()     │    !     │     !      │    ✓     │      ✓       ┃
+┃ contains() │    ✓     │     ✓      │    ✓     │      ✓       ┃
+┃ len()      │          │     !      │    !     │      !       ┃
+┃ getitem()  │          │            │    !     │      !       ┃
+┃ reversed() │          │            │    ✓     │      ✓       ┃
+┃ reverse()  │          │            │          │      ✓       ┃
+┃ index()    │          │            │          │      ✓       ┃
+┃ count()    │          │            │          │      ✓       ┃
 ┗━━━━━━━━━━━━┷━━━━━━━━━━┷━━━━━━━━━━━━┷━━━━━━━━━━┷━━━━━━━━━━━━━━┛

#Enum

diff --git a/parse.js b/parse.js index 6498c55..3ba07ff 100755 --- a/parse.js +++ b/parse.js @@ -172,20 +172,28 @@ const DIAGRAM_7_A = '+------------+----------+------------+----------+--------------+\n' + '| | Iterable | Collection | Sequence | abc.Sequence |\n' + '+------------+----------+------------+----------+--------------+\n' + - '| iter() | yes | yes | yes | yes |\n' + - '| len() | | yes | yes | yes |\n' + - '| getitem() | | | yes | yes |\n' + - '| contains() | | yes | | yes |\n' + + '| iter() | REQ | REQ | yes | yes |\n' + + '| contains() | yes | yes | yes | yes |\n' + + '| len() | | REQ | REQ | REQ |\n' + + '| getitem() | | | REQ | REQ |\n' + + '| reversed() | | | yes | yes |\n' + + '| reverse() | | | | yes |\n' + + '| index() | | | | yes |\n' + + '| count() | | | | yes |\n' + '+------------+----------+------------+----------+--------------+\n'; const DIAGRAM_7_B = '┏━━━━━━━━━━━━┯━━━━━━━━━━┯━━━━━━━━━━━━┯━━━━━━━━━━┯━━━━━━━━━━━━━━┓\n' + '┃ │ Iterable │ Collection │ Sequence │ abc.Sequence ┃\n' + '┠────────────┼──────────┼────────────┼──────────┼──────────────┨\n' + - '┃ iter() │ ✓ │ ✓ │ ✓ │ ✓ ┃\n' + - '┃ len() │ │ ✓ │ ✓ │ ✓ ┃\n' + - '┃ getitem() │ │ + │ ✓ │ ✓ ┃\n' + - '┃ contains() │ │ ✓ │ │ ✓ ┃\n' + + '┃ iter() │ ! │ ! │ ✓ │ ✓ ┃\n' + + '┃ contains() │ ✓ │ ✓ │ ✓ │ ✓ ┃\n' + + '┃ len() │ │ ! │ ! │ ! ┃\n' + + '┃ getitem() │ │ │ ! │ ! ┃\n' + + '┃ reversed() │ │ │ ✓ │ ✓ ┃\n' + + '┃ reverse() │ │ │ │ ✓ ┃\n' + + '┃ index() │ │ │ │ ✓ ┃\n' + + '┃ count() │ │ │ │ ✓ ┃\n' + '┗━━━━━━━━━━━━┷━━━━━━━━━━┷━━━━━━━━━━━━┷━━━━━━━━━━┷━━━━━━━━━━━━━━┛\n'; diff --git a/web/script_2.js b/web/script_2.js index 4e73ed3..8e211e3 100644 --- a/web/script_2.js +++ b/web/script_2.js @@ -140,10 +140,14 @@ const DIAGRAM_7_A = '+------------+----------+------------+----------+--------------+\n' + '| | Iterable | Collection | Sequence | abc.Sequence |\n' + '+------------+----------+------------+----------+--------------+\n' + - '| iter() | yes | yes | yes | yes |\n' + - '| len() | | yes | yes | yes |\n' + - '| getitem() | | | yes | yes |\n' + - '| contains() | | yes | | yes |\n' + + '| iter() | REQ | REQ | yes | yes |\n' + + '| contains() | yes | yes | yes | yes |\n' + + '| len() | | REQ | REQ | REQ |\n' + + '| getitem() | | | REQ | REQ |\n' + + '| reversed() | | | yes | yes |\n' + + '| reverse() | | | | yes |\n' + + '| index() | | | | yes |\n' + + '| count() | | | | yes |\n' + '+------------+----------+------------+----------+--------------+\n'; const DIAGRAM_7_B =