在另一个用户定义的函数中调用用户定义的函数时发生名称错误

Question

我需要编写一个程序，用于打开并读取文件并包含单独的用户定义函数，用于计算文件中的行数和单词数量，例如linecount（），wordcount（）等。我草拟了下面的代码，但是我一直得到一个名称错误，说“全局名称f'未定义”。 f是应该由openfile（）函数返回的文件句柄。有任何建议吗？

#open and read file 
def openfile(): 
    import string 
    name = raw_input ("enter file name: ") 
    f = open (name) 

# Calculates the number of paragraphs within the file 
def linecount(): 
    openfile() 
    lines = 0 
    for line in f: 
     lines = lines + 1 
    return lines 

#call function that counts lines 
linecount() 

Answer 1

因为f是OPENFILE局部变量

def openfile(): 
    import string 
    name = raw_input ("enter file name: ") 
    return open (name) 

# Calculates the number of paragraphs within the file 
def linecount(): 
    f = openfile() 
    lines = 0 
    for line in f: 
     lines = lines + 1 
    return lines 

，甚至更短的

def file_line_count(): 
    file_name = raw_input("enter file name: ") 
    with open(file_name, 'r') as f: 
     return sum(1 for line in f)