將部分列表傳遞給Python函數

Question

我正在編寫一個Python程序來讀取文本文件並提取一些信息。我試圖找到三個項目，一個實數和兩個列表。該腳本將文本文件的行存儲爲列表inLines。在閱讀腳本時，腳本使用for curLine in inLines:，然後在所有行中搜索特定的鍵。找到搜索關鍵字後，我想將inLines的剩餘部分傳遞給一個函數，再讀幾行，然後返回到函數停止行的主腳本。

這裏是什麼，我希望發生的事情（給出意見代碼指令）

line of text that doesn't matter #Read by main, nothing interesting happens 
line of text that doesn't matter #Read by main, nothing interesting happens 
search key A      #Read by main, all following lines passed to function A 
line that matters     #Read by function A, stores in object 
line that matters     #Read by function A, stores in object 

line that matters     #Read by function A, stores in object 


search key B      #Read by function A, return to main, all following lines passed to function B 


line that matters     #Read by function B, stores in object 

search key C      #Read by function B, return to main, all following lines passed to function C 
line that matters     #Red by function C, stores in object 

所以每個搜索鍵告訴其功能是在程序（和不同的密鑰可以以任意順序一個小圖）當腳本找到該鍵時，它將所有更多的行傳遞給正確的函數，並且每當函數找到一個搜索鍵時，它就會中斷，並將所有其他行傳回主（然後將相同的行傳遞給相應的函數）

對不起，這本書的一個問題，我剛剛學習了多年FORTRAN之後的Python，所以如果任何人都能想到更好的方法來解決這個問題，我願意提供建議。在此先感謝

Answer 1

這個小腳本是關閉到你想要的。它放棄在指定搜索功能之前發生的行。你應該能夠適應你的需求。

import sys 


def search_func_a(l): 
    """ 
    Called for things that follow `search key A` 
    """ 
    print 'A: %s' % l 


def search_func_b(l): 
    """ 
    Called for things that follow `search key B` 
    """ 
    print 'B: %s' % l 


def search_key_func(l): 
    """ 
    Returns the associated "search function" for each search string. 
    """ 
    if 'search key A' in l: 
     return search_func_a 
    if 'search key B' in l: 
     return search_func_b 
    return None 


def main(): 
    # Start with a default handler. This changes as `search key` lines are 
    # found. 
    handler = lambda _: 0 

    for line in open('test.txt'): 
     # search_key_func returns None for non `search key` lines. In that 
     # case, continue to use the last `search function` found. 
     search_func = search_key_func(line) 
     if search_func: 
      # If a search line is found, don't pass it into the search func. 
      handler = search_func 
      continue 
     handler(line) 


if __name__ == '__main__': 
    sys.exit(main()) 

Answer 2

是否有這樣做的問題？

inA = inB = inC = False 
for line in file: 
    if keyA(line): 
    inA = True 
    inB = inC = False 
    elif keyB(line): 
    inB = True 
    inA = inC = False 
    elif keyC(line): 
    inC = True 
    inA = inB = False 
    if inA: 
    processA(line) 
    if inB: 
    processB(line) 
    if inC: 
    processC(line) 

你是問，如果有一些更快的方法？

Answer 3

#!/usr/bin/env python3 
# encoding: utf-8 

import sys 

def find(haystack, needle, start_line = 0): 
    for i, line in enumerate(haystack[start_line:]): 
     if line == needle: 
      return i + 1 
    raise("%s not found." % needle) 

def main(argv = None): 
    if argv is None: 
     argv = sys.argv 

    with open(argv[1], 'r') as f: 
     text = f.read().splittext() 

    find(text, "c", find(text, "b", find(text, "a"))) 

if __name__ == "__main__": 
    sys.exit(main()) 

我不知道你是什麼意思「在對象存儲」，但代碼很容易修改，以滿足您的目的。