何时应重构以避免全局变量？[关闭]

问：

据我了解，在简单程序中有选择地使用全局变量是可以的——但作为初学者，我不知道究竟什么是“选择性”或“简单”。

我的 Notepad++ 脚本遍历每个打开的文件，检查可用于打开其相关文件的正则表达式模式。然后检查此打开的文件是否存在正则表达式模式，这些模式可用于相应地调整原始文件，从而允许用户在需要时手动识别文件。它在 2-3 个函数中使用 5 个全局变量。

是否应该重构代码以避免这种情况？如果是这样，最好的方法是什么？

# encoding=utf-8
import os
import re

from Npp import *


history_files = 'C:/Program Files (x86)/Steam/steamapps/common/Europa Universalis IV/history/countries'

options = '1 - Eastern European\n2 - Anatolian\n3 - Muslim\n4 - Indian\n' + (
    '5 - East African\n6 - Central African\n7 - Chinese\n8 - Nomad\n' +
    '9 - West African\n10 - North American\n11 - Mesoamerican\n' +
    '12 - South American\n13 - Andean\n14 - Aboriginal\n15 - Polynesian\n')

maluses = {
    'eastern': (20, 1), 
    'ottoman': (25, 2), 
    'muslim': (37.5, 3), 
    'indian': (40, 4),
    'east_african': (45, 5), 
    'central_african': (55, 6),
    'chinese': (50, 7), 
    'nomad_group': (62.5, 8),
    'sub_saharan': (50, 9), 
    'mesoamerican': (75, 11), 
    'andean': (75, 13), 
    'north_american': (92.5, 10), 
    'south_american': (92.5, 12), 
    'aboriginal_tech': (92.5, 14), 
    'polynesian_tech': (92.5, 15),
}


def message(text, style):
    current_file = re.compile(r'[^\\]*\.txt').search(filename).group(0)
    console.editor.setReadOnly(False)
    console.editor.addStyledText(Cell('\n"' + current_file + '" ' + text, [style]))


def replace(percentage):
    percentage_as_factor = float((100 - float(percentage)) * 0.01)
    base_tech = 3
    editor.rereplace(r'(?<=adm_tech = )(\d+)|(?<=dip_tech = )(\d+)|(?<=mil_tech = )(\d+)', (
        str(int(round(base_tech * ((((float(value.group(0)) / base_tech) - 1) * percentage_as_factor) + 1))))));
    notepad.save()


def adjust(tag):
    if tag in ('mission_tag', 'decision_tag'):
        message(tag + ' matched to "' + matched_file + '"', 0)
        notepad.open(history_files + '\\' + matched_file)
        tech = (re.search(r'(?<=technology_group = )(\w+)', editor.getText())).group(0)
        notepad.close()
    elif tag == 'manual':
        raw_tech = str([key for key, dict_value in maluses.items() if int(prompt) in dict_value])
        tech = re.search(r"[^[\]']+", raw_tech).group(0)
        message('manually matched to "' + tech + '"', 0)
    else:
        raise Exception()

    if tech in maluses:
        replace(maluses[tech][0])
        message('- "' + tech + '" matched to key in dictionary - value adjusted\n', 0)
    elif tech == 'western':
        message('is "western"\n', 5)
    else: 
        message('"' + tech + '" not found in dictionary', 1)
    return



def adjust_tech_patterns():
    editor.beginUndoAction()
    global filename
    for (filename, bufferID, index, view) in notepad.getFiles():
        notepad.activateBufferID(bufferID)
        global value
        value = re.search(r'(?<=adm_tech = )(\d+)|(?<=dip_tech = )(\d+)|(?<=mil_tech = )(\d+)', editor.getText())
        if not value:
            message('exited the loop because of "no value"\n', 5)
            continue

        mission_tag = re.search(r'\s*potential = \{[\s\S]*?(?<=tag = )((?!ROOT)\w+)', editor.getText())
        decision_tag = re.search(r'(?<=NOT = { exists = )((?!ROOT)\w+)', editor.getText())

        if mission_tag:
            mission_tag_compiled = (re.compile(mission_tag.group(1)))
            global matched_file
            (matched_file,) = filter(mission_tag_compiled.match, os.listdir(history_files))
            adjust('mission_tag')
            continue
        elif decision_tag:
            decision_tag_compiled = (re.compile(decision_tag.group(1)))
            global matched_file
            (matched_file,) = filter(decision_tag_compiled.match, os.listdir(history_files))
            adjust('decision_tag')
            continue
        else:
            message('has no identifiers', 4)
            notepad.new()
            editor.addText(options)
            editor.setSavePoint()
            current_file = re.compile(r'[^\\]*\.txt').search(filename).group(0)
            global prompt
            prompt = notepad.prompt('What tech group is "' + current_file[:-4] + '"?', '','')
            notepad.close()

            if prompt in (None, ''):
                continue
            adjust('manual')
          
    editor.endUndoAction()


adjust_tech_patterns()