Question

python formatter 既有单引号又有双引号

formatter = "%r %r %r %r"

print formatter % (1,2,3,4,)
print formatter % ("one","two", "three", "four")
print formatter % (True, False, False, True)
print formatter % (formatter, formatter, formatter, formatter)
print formatter %(
"I had this thing.",
"That you could type up right.",
"But it didn't sing.",
"So I said goodnight."
)

为什么在最后四句话输出的时候只有第三句有双引号
1 2 3 4
'one' 'two' 'three' 'four'
True False False True
'%r %r %r %r' '%r %r %r %r' '%r %r %r %r' '%r %r %r %r'
'I had this thing.' 'That you could type up right.' "But it didn't sing." 'So I said goodnight.'

Answer 1

这是嵌套关系，因为在But it didn't sing.里面有单引号了，所以外面必须用双引号。