python - 双 for 循环列表理解

Question

我正在尝试使用列表理解执行以下操作:

Input: [['hello ', 'world '],['foo ',' bar']]
Output: [['hello', 'world'], ['foo', 'bar']]

以下是在没有列表推导的情况下如何做到这一点:

a = [['hello ', 'world '],['foo ',' bar']]
b = []

for i in a:
   temp = []
   for j in i:
      temp.append( j.strip() )
      b.append( temp )

print(b)
#[['hello', 'world'], ['foo', 'bar']]

如何使用列表推导式来做到这一点？

Answer 1

a = [['hello ', 'world '],['foo ',' bar']]
b = [[s.strip() for s in l] for l in a]
print(b)
# [['hello', 'world'], ['foo', 'bar']]