Python: Joining tuples with backslash

Question

I'm attempting to join a tuple of two strings using the .join method as follows.

>>> my_tuple = ("parent", "child")
>>> "\\".join(my_tuple)

I would expect this to return parent\child, however, it returns parent\\child.

Why is this? Escaping the backslash with another backslash works fine if I attempt to simply print it.

>>> print "parent\\child"
>>> parent\child

Observed in Python 2.7.3 on Windows 7.

[str vs. repr](http://stackoverflow.com/questions/1436703/difference-between-str-and-repr-in-python) -- the first is using the `repr` of the string, which always includes escapes for unambiguity. — nmclean, Apr 03 '14 at 11:45

score 4 · Accepted Answer · answered Apr 03 '14 at 11:36

4

You got that right, it's only printing a double backslash because you are not printing it:

>>> '\\'.join(my_tuple)
'parent\\child'
>>> print '\\'.join(my_tuple)
parent\child

it's the same difference than __str__ and __repr__:

>>> '\\'.__repr__()
"'\\\\'"
>>> '\\'.__str__()
'\\'

answered Apr 03 '14 at 11:36

fredtantini

So the escaping only occurs when printed, and not whilst it's stored in a variable or similar? Interesting, thanks! – Evidex Apr 03 '14 at 11:39
The stored value is the same, but the representation of one backslash is `\\\`. – Matthias Apr 03 '14 at 11:42
1

@Evidex compare `'\n'` and `print '\n'` for instance. – fredtantini Apr 03 '14 at 11:42

1 Answers1