python - Quotes within quotes -


in python 3.x:

    print(""s"")       # syntaxerror     print("""s""")     # prints s     print(""""s"""")   # syntaxerror     print("""""s""""") # prints ""s

what reason behind different behaviour, when there different numbers of double quotes in string?

in python can create multiline strings """...""". quoting documentation strings,

string literals can span multiple lines. 1 way using triple-quotes: """...""" or '''...'''.

in first case, ""s"" parsed this

"" (empty string literal)  s  "" (empty string literal)

now, python doesn't know s. why failing syntaxerror.

in third case, string parsed this

"""  "s  """ (end of multiline string)  `"`

now last " has no matching ". why failing.

in last case, """""s""""" parsed this

"""  ""s  """  ""

so, multiline string parsed , have empty string literal next it. in python, can concatenate 2 string literals, writing them next each other, this

print ("a" "b") # ab

so, last empty string literal concatenated ""s.


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