This is the 24th day of my participation in Gwen Challenge

Requirements describe

If you need to implement a random-generated recipe for three meals, offer both random-generated or custom random-generated options, as far as possible from Pythonic. For example, we can call it like this:

breakfast >> lunch >> dinner
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Demand analysis

The syntax implementation of >> requires the use of __rshift and __rrshift. For specific usage, please refer to the previous two tweets. Rrshift Python implements Linux pipes

  1. Customize a list of meals as a random selection
  2. If it is all randomly generated, no parameter is passed and steps 4 and 5 are carried out
  3. The result of breakfast is passed to lunch, and lunch is inserted based on the result of breakfast
  4. Pass the result of lunch to Dinner, insert dinner at the base of the result of lunch
  5. If it is custom and random, a function is required to record the parameters and repeat step 45

Implement >> pipe syntax

For syntax examples, see rrshift Python’s Magic method for implementing Linux pipes in Python

# -*- coding=utf-8 -*-
import functools
import random
import pprint

class Pipe:

    def __init__(self, function) :
        self.function = function
        functools.update_wrapper(self, function)

    # when one of the >> sides does not implement __rshift__
    def __rrshift__(self, other) :
        return self.function(other)

    # implementation carries custom parameters
    def curry(self, *args, **kwargs) :
        return Pipe(lambda x: self.function(x, *args, **kwargs))
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Menu waiting for objects

breakfast_menu = ['bacon'.'egg'.'milk'.'porridge'.'bread'.'corn']
lunch_menu = ['fish'.'beef'.'chicken'.'radish'.'spinach'.'watercress']
dinner_menu = ['lean meat'.'mutton'.'celery'.'tofu'.'cucumber']
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Menu random implementation

@Pipe
def breakfast(menu, *args, **kwargs) :
    menu['breakfast'] = random.sample(breakfast_menu, 3 if args == (' '.)else 3 - len(args))
    if not args == (' ',) :for custom in args:
            menu['breakfast'].append(custom)
    return menu


@Pipe
def lunch(menu, *args, **kwargs) :
    menu['lunch'] = random.sample(lunch_menu, 3 if args == (' '.)else 3 - len(args))
    if not args == (' ',) :for custom in args:
            menu['lunch'].append(custom)
    return menu


@Pipe
def dinner(menu, *args, **kwargs) :
    menu['dinner'] = random.sample(dinner_menu, 3 if args == (' '.)else 3 - len(args))
    if not args == (' ',) :for custom in args:
            menu['dinner'].append(custom)
    return menu
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Overall control and pipeline implementation

if __name__ == "__main__":
    # menu stores the menu
    menu = dict()

    random_choice = int(input("Is the menu automatically generated? Yes: 1 No: 0\n"))
    # Automatic random generation
    if random_choice:
        pprint.print(menu >> breakfast >> lunch >> dinner)
    # Custom menu, pass parameters
    else:
        breakfast_custom_list = input("Breakfast menu (3 items at most), not 3 items left, random generation:").split(' ')
        lunch_custom_list = input("Lunch menu (3 items at most), not 3 items left, random generation:").split(' ')
        dinner_custom_list = input("Dinner menu (3 items at most), not 3 items left, random generation:").split(' ')

        [1,2,3] => 1,2,3
        breakfast = breakfast.curry(*(breakfast_custom_list))
        lunch = lunch.curry(*(lunch_custom_list))
        dinner = dinner.curry(*(dinner_custom_list))

        The output of the beautiful format is not done, directly print
        pprint.print(menu >> breakfast >> lunch >> dinner)
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Randomly generated effect

Are menus automatically generated? Is: 1 no: 0 1 {' breakfast ': [' bread', 'egg', 'how'], 'dinner' : [' now ', 'cucumber', 'lean meat'], 'lunch' : ['spinach', 'chicken', 'fish']}Copy the code

Custom menu generation effect

Are menus automatically generated? Yes: 1 No: 0 0 Breakfast menu (maximum 3 items), not enough 3 items, left random generation: sweet potato corn porridge lunch menu (maximum 3 items), not enough 3 items, left random generation: dinner menu (maximum 3 items), not enough 3 items, left random generation: loofah soup {'breakfast': [' sweet potato ', 'corn', 'white porridge'], 'dinner' : [' now ', 'cucumber', 'towel gourd soup'], 'lunch' : [' beef ', 'fish', 'radish']}Copy the code

Implementation of carrying parameters

# implementation carries custom parameters
    def curry(self, *args, **kwargs) :
        return Pipe(lambda x: self.function(x, *args, **kwargs))
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How it works: The *args and **kwargs of anonymous functions hold the parameters that need to be carried.

Other syntax, not mentioned, welcome message communication