get string how it is defined

[bhojendra]

I can have any characters inside the string. For eg.

str = "some\" quoted value'foo"
print(str)
# some" quoted value'foo

How can I get it printed intact?

# some\" quoted value'foo

[Gribouillis]

The point is that there are several ways to represent literally a string. The general idea is to use repr()

>>> s = "some \" quo\u0074ed value'foo"
>>> print(repr(s))
'some " quoted value\'foo'

You cannot be 100% sure to recover the initial form because the compiler interpretes the string and it doesn't remember that the " was initially escaped and ' was not for example, or that t was written \u0074

[bhojendra]

Ah, that doesn't help me. What I'm trying to do is combine that string in previous string. For eg.

str = "{a:"
str += "some \" quoted value'foo"
str += "}"

Which should result in:

# {a:"some \" quoted value'foo"}
# But not:
# {a:"some " quoted value\'foo"}

So, what I want is what user has inputed exactly.

[perfringo]

Never use str as name. Otherwise you can find yourself wondering:

In [1]: str(100)                                                                
Out[1]: '100'

In [2]: str = "some\" quoted value'foo"                                         

In [3]: str(100)                                                                
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-3-1aa51eeeed3a> in <module>
----> 1 str(100)

TypeError: 'str' object is not callable

[Gribouillis]

You need to understand that when you write

s = "some \" quoted value 'foo"

the string s doesn't contain any \ character. It means that your requirement that "it should result in" a string with a backslash character is not well defined. You'll have to write your own escaping function and implement your own rules, for example you could replace all the " in a string with \".

[bhojendra]

I may not know what user may post in their inputs. So, it's hard know what to replace. Or, is it just fine to replace all backslashes?

[buran]

your post is example of classical XY problem in my view. it looks like you try to construct json string/file and doing so the wrong way.

[perfringo]

As Griboullis explained there are subtle differences how string stored and how it's printed out:

>>> backslash = '\\'
>>> a = "{a:"
>>> a += f"some {backslash}\" quoted value'foo"
>>> a += "}"
>>> print(a)
{a:some \" quoted value'foo}
>>> a
'{a:some \\" quoted value\'foo}'

[buran]

import json
foo = "some\" quoted value'foo"
spam = {'a':foo}
json_str = json.dumps(spam)
print(json_str)

Output:
{"a": "some\" quoted value'foo"}

[bhojendra]

Ah, this works just fine! Thanks. Was forgetting about dumps. How can I mark your answer as solution?