Das deutsche Python-Forum

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#!/usr/bin/env python
# -*- coding: utf-8 -*-

# Simple program to store some notes

FILENAME = "notes.txt"  # must be in working directory

# make sure file exists
try:
    f = open(FILENAME, "r")
    f.close()
except FileNotFoundError:
    f = open(FILENAME, "w")
    f.close()
        
def print_notes():
    with open(FILENAME, "r") as file:
        print("Notes so far:")
        while True:
            line = file.readline()
            if len(line) == 0:
                break
            print(line, end="")
    
def write_note(note):
    with open(FILENAME, "a") as file:
        if not note.isspace():
            file.write(note + "\n")
    
def delete_notes():
    with open(FILENAME, "w") as file:
        print("Notes successfully deleted.")

def main():
    print("=== Note Manager ===")
    print("'show': print all" \
          ", 'del': delete all, 'done': quit.\n\n")
    
    while True:
        note = input("Enter note or command: ")
        if note == "done":
            break
        elif note == "show":
            print_notes()
        elif note == "delete":
            delete_notes()
        else:
            write_note(note)
        
if __name__ == "__main__":
    main()

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In [6]: FileNotFoundError
---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
/home/bj/<ipython-input-6-32843a8d74dd> in <module>()
----> 1 FileNotFoundError

NameError: name 'FileNotFoundError' is not defined

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def print_notes():
    print('Notes so far:')
    with open(FILENAME, 'r') as lines:
        sys.stdout.writelines(lines)

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f = open("qwertz.txt", "r")

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Traceback (most recent call last):
  File "D:\Python\Scripts\Notes\Notes.py", line 49, in <module>
    main()
  File "D:\Python\Scripts\Notes\Notes.py", line 42, in main
    print_notes()
  File "D:\Python\Scripts\Notes\Notes.py", line 21, in print_notes
    sys.stdout.writelines(file)
AttributeError: closed

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def add_entry():
    print("Eintrag wird hinzugefügt")

def search_entry():
    print("Eintrag wird gesucht")

def remove_entry():
    print("Eintrag wird gelöscht")

def quit():
    print("Beende das Programm")

def load():
    print("Datensatz wird geladen")

def save():
    print("Datensatz wird gespeichert")

def handle_menu(menu):
    while True:
        for index, item in enumerate(menu, 1):
            print("{}  {}".format(index, item[0]))
        choice = int(input("Ihre Wahl? ")) - 1
        if 0 <= choice < len(menu):
            menu[choice][1]()
        else:
            print("Bitte nur Zahlen im Bereich 1 - {} eingeben".format(
                                                                    len(menu)))

menu = [
    ["Eintrag hinzufügen", add_entry],
    ["Eintrag löschen", remove_entry],
    ["Eintrag suchen", search_entry],
    ["Telefonbuch laden", load],
    ["Telefonbuch speichern", save],
    ["Beenden", quit]
]

handle_menu(menu)

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menu[index][1]()

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def func_with_param(adresses):
    # do something with param

def another_func_with_same_param(adresses):
    # do something with param

def func_without(*args):
    # do something *without* using params!
    # we just ignore it!

# die Funktionen einfach *immer* mit Parameter aufrufen
menu[index](adresses)

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from functools import partial

def func_1(arg):
    print(arg)

adresses = [
    {"name": "Foo", "town": "FooTown"},
    {"name": "Bar", "town": "BarTown"}
]

func_1_call = partial(func_1, adresses)
# func_1_call trägst Du in die Menüstruktur ein!

# eigentlich durch ``menu[index]()``
func_1()_call()
> [{'town': 'FooTown', 'name': 'Foo'}, {'town': 'BarTown', 'name': 'Bar'}]

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adresses.append({"name": "FooBar", "town": "FooBarTown"})

func_1_call()
> [{'town': 'FooTown', 'name': 'Foo'}, {'town': 'BarTown', 'name': 'Bar'}, {'town': 'FooBarTown', 'name': 'FooBar'}]