PyTlin 1.2

Kotlin functions also, let, and run, as well as sh-like (and Mathematica-like) piping syntax

PyTlin

Module implementing the Kotlin functions also, let, and run in Python. Additionally it includes sh-like (and Mathematica-like) piping syntax.

The Kotlin functions are documented in here.

Install

pip install PyTlin

Syntax

from PyTlin import k

k(obj).let(func).also(func)
k.run(func)
k(obj) | func1 | func2 | ...
k(obj) @ func1 @ func2 @ ...

Here all expressions (except k.run(func)) is wrapped in the class k. To recover obj one can apply either of these

k(obj).end
k(obj) | 'end'
k(obj) | 0
k(obj) @ 'end'
k(obj) @ 0

Example

from PyTlin import k
class Person:
    def __init__(self,name,age):
        self.name = name
        self.age = age
    def __repr__(self):
        return '%s, %d' % (self.name, self.age)
    def increaseAge(self):
        self.age = self.age + 1
    def nameToUpperCase(self):
        self.name = self.name.upper()

student = Person('Pete', 18)
print(student) #Pete, 18

let

name = k(student).let(lambda x: (print(x),x.name)[1]) #Pete, 18
print(name) #Pete

also

newstudent = k(student).also(lambda x: (x.increaseAge(), x.nameToUpperCase()))
print(newstudent) #PETE, 19

run

mood = 'sad'
k.run(lambda mood = 'happy': print(mood)) #happy
print(mood) #sad

Piping

Piping can be done with either .let or with pipe operators @ (Mathematica-like in reverse order) or | (sh-like).

ops=k(4).let(lambda x: x*2).let(lambda x: x+3)
print(ops) #11
print(type(ops)) #<class 'PyTlin.k'>
print(ops.end) #11
print(type(ops.end)) #<class 'int'>

print(ops.end ==
 k(4) @ (lambda x: x*2) @ (lambda x: x+3) @ 'end') #True

print(ops.end ==
 k(4) | (lambda x: x*2) | (lambda x: x+3) | 0) #True