boxcat 0.0.5

small playground library for fp in python

boxcat

A small playground library for fp in Python, inspired from my time writing Scala

Development testing

pytest

Usage

---

Options

To wrap values in Option monad

option_ten = Option(10)
option_string = Option("hello")
option_bool = Option(True)

.map()

Integer example

option_ten = Option(10)
option_multiply_by_two = option_ten.map(lambda x: x * 2)
print(option_multiply_by_two.get_or_else(0))

result:
20

String example

option_hello_world = Option("hello world")
option_uppercase = option_hello_world.map(lambda s: s.upper())


print(option_uppercase.get_or_else(""))

result:
HELLO WORLD

.unsafe_get()

To get the value out of the Option

option_hello_world = Option("just give me the value I know it's there")

print(option_hello_world.unsafe_get())

result:
"just give me the value I know it's there"

---

Seq

So there isn't a great way to my knowledge of adding extension methods in Python There was a thing called Monkey-Patching but seemed dodgy.

We can wrap traditional Lists [] in Seq()

seq_empty = Seq([])
seq_ten = Seq([10])
seq_string = Seq(['hello', 'world'])
seq_bool = Seq([True])

my_list = [1, 'a', 2, 'b', 3, 'c', 4, 'd', 5, 'e', 6, 'f', 7, 'g' 8, 'h', 9, 'i', 10]

seq_my_list = Seq(my_list)

Important!!

.to_list()

Use .to_list() to get back the original Python List type from Seq()

my_list = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

seq_my_list = Seq(my_list)

back_to_python_list = seq_my_list.to_list()

print(back_to_python_list)

result:
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

.map()

Integer example

my_list = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

seq_my_list = Seq(my_list)

seq_add_one = seq_my_list.map(lambda x: x + 1)
print(seq_add_one.to_list)

result:
[2, 3, 4, 5, 6, 7, 8, 9, 10, 11]

.filter()

my_list = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

seq_numbers = Seq(my_list)

only_evens = seq_numbers.filter(lambda x: x % 2 == 0)
print(seq_add_one.to_list)

result:
[2, 4, 6, 8, 10]