Question

我有一长串要定义的变量（~100）。定义如下：

provider = node.xpath("//provider/text()")[0]
language = node.xpath("//language/text()")[0]
subtype = node.xpath("//subtype/text()")[0]
etc...

我如何更简洁地定义它/ DRY，类似于

COLUMN_VARIABLES = ['provider', 'language','subtype']

for variable in COLUMN_VARIABLES:
    variable = node.xpath("//%s/text()"%variable)[0]

Answer 1

更简洁的方法是使用字典：

COLUMN_VARIABLES = ['provider', 'language','subtype']
data = {}

for variable in COLUMN_VARIABLES:
    data[variable] = node.xpath("//%s/text()"%variable)[0]

专业提示：每当你发现自己想要使用变量变量名时，就意味着你不需要变量，你希望一个容器代替所有数据。

Answer 2

使用词典：

COLUMN_VARIABLES = ['provider', 'language','subtype']

vars = {}    
for variable in COLUMN_VARIABLES:
    vars[variable] = node.xpath("//%s/text()"%variable)[0]

Answer 3

使用dict保存结果：

column_vars = ['provider', 'language','subtype']
nodes = {}

for var in column_vars:
    nodes[var] = node.xpath("//%s/text()" % variable)[0]

在python中定义一长串变量

3 个答案: