More on functional features

tinylambda · tinylambda · commit 49bae4fc8c3e · 2020-08-18T18:50:07.000+08:00
diff --git a/functional_program/functional_features/functional_generator.py b/functional_program/functional_features/functional_generator.py
@@ -0,0 +1,25 @@
+import math
+from typing import Iterator
+
+
+def pfactorsl(x: int) -> Iterator[int]:
+    if x % 2 == 0:
+        yield 2
+        if x // 2 > 1:
+            yield from pfactorsl(x // 2)
+        return
+    for i in range(3, int(math.sqrt(x) + .5) + 1, 2):
+        if x % i == 0:
+            yield i
+            if x // i > 1:
+                yield from pfactorsl(x // i)
+            return
+    yield x
+
+
+if __name__ == '__main__':
+    print([item for item in pfactorsl(100000)])
+
+
+
+
diff --git a/functional_program/functional_features/functional_reuse_iterable.py b/functional_program/functional_features/functional_reuse_iterable.py
@@ -0,0 +1,18 @@
+import itertools
+from typing import Iterable, Any
+
+
+def limits(iterable: Iterable[Any]) -> Any:
+    max_tee, min_tee = itertools.tee(iterable, 2)
+    return max(max_tee), min(min_tee)
+
+
+def numbers():
+    for i in range(10):
+        yield i
+
+
+if __name__ == '__main__':
+    ns = numbers()
+    print(limits(ns))
+
diff --git a/functional_program/functional_features/functional_str.py b/functional_program/functional_features/functional_str.py
@@ -0,0 +1,45 @@
+from decimal import *
+from typing import Text, Optional
+
+
+def clean_decimal(text: Text) -> Optional[Text]:
+    if text is None:
+        return None
+    return Decimal(
+        text.replace('$', '').replace(',', '')
+    )
+
+
+def replace(s: Text, a: Text, b: Text):
+    return s.replace(a, b)
+
+
+def clean_decimal_v2(text: Text) -> Optional[Text]:
+    if text is None:
+        return None
+    return Decimal(
+        replace(replace(text, '$', ''), ',', '')
+    )
+
+
+def remove(s: Text, chars: Text) -> Text:
+    if chars:
+        return remove(
+            s.replace(chars[0], ''),
+            chars[1:]
+        )
+    return s
+
+
+def clean_decimal_v3(text: Text) -> Optional[Text]:
+    if text is None:
+        return None
+    return Decimal(remove(text, '$,'))
+
+
+if __name__ == '__main__':
+    s_: Text = '$100,000.1'
+    print(clean_decimal(s_))
+    print(clean_decimal_v2(s_))
+    print(clean_decimal_v3(s_))
+
diff --git a/functional_program/functional_features/functional_tuple.py b/functional_program/functional_features/functional_tuple.py
@@ -0,0 +1,27 @@
+from typing import Tuple, Callable, NamedTuple
+from collections import namedtuple
+
+
+example_rgb = (128, 152, 64)
+
+RGB = Tuple[int, int, int]
+red: Callable[[RGB], int] = lambda color: color[0]
+print(example_rgb, red(example_rgb))
+
+
+Color = namedtuple('Color', 'red green blue name')
+example_color = Color(red=128, green=152, blue=64, name='name_1')
+print(example_color, example_color.red)
+
+
+class Color(NamedTuple):
+    """RGB color"""
+    red: int
+    green: int
+    blue: int
+    name: str
+
+
+example_color = Color(red=128, green=152, blue=64, name='name_2')
+print(example_color, example_color.red)
+
