Python - 全局变量小记

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数组

数组可以 append，不能 +

vids = ['a', 'b']

def t1():
    print('-- vids : ', vids) 

    vids.append('c')
    print('-- vids : ', vids) 

    vids += 'd' # 报错
    print('-- vids : ', vids) 
 

t1() 
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没问题

def t3():
    
    global vids
    vids += 'd' # 报错
    print('-- vids : ', vids) 
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字符

a = '1'
def t2():
    global a
    a = '2' 
    print('-- a : ', a) 
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a = '1'
def t2():

    print('-- a : ', a) 
    # 报错 : SyntaxError: name 'a' is used prior to global declaration
    
    global a
    a = '2' 
    
    print('-- a : ', a) 
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a = '1'
def t2():
    global a = '2' # 报错
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使用模块化实现全局变量：

​​import​​​ ​​global_var_model as gl​​ 
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https://blog.51cto.com/xiaohaiwa/5683078