Remove \n from triple quoted string in python

Question

I have the following string:

string = """
Hello World
123
HelloWorld
"""

I want to clear all the line-breaks from the string in python.

I tried

string.strip()

But it's not working as desired.

What I should do?

I'm using python 3.3

Thanks.

Solution 1

str.strip removes whitespace from the start and the end of the string.

>>> string
'\nHello World\n123\nHelloWorld\n'
>>> string.strip()
'Hello World\n123\nHelloWorld'

If you want to remove the new line characters inside of the string, you can replace them by something else using str.replace:

>>> string.replace('\n', ' ')
' Hello World 123 HelloWorld '

Solution 2

I would like to point out that, depending on how that triple-quoted string is being used, you could avoid the issue entirely.

In Python triple-quoted strings, you can put a backslash ("\") at the end of a line to ignore the line break. In other words, you can use it to put a line break at that spot in your code without making a line break in your string.

For example:

"""line 1 \
line 2 \
line 3"""

will actually become

line 1 line 2 line 3

if printed or written to some file or other output.

Using it this way can eliminate any need for a function to replace the line breaks, making your code clearer and cleaner.

EDIT:

If you're using backslash line continuations like this, you can also use simple single-quoted strings the same way;

"line 1 \
line 2 \
line 3"

is also equivalent to

line 1 line 2 line 3

Solution 3

Use translate instead of replace for this kind of operation.

>> string.translate(None, "\n")
Hello World123HelloWorld

You will realize how fast translate is when you work with big files.

Comments

[poke]

That’s no different to print(string.strip()).

[shad0w_wa1k3r]

But what if he wants to use individual lines?

[poke]

That would be a different problem and nothing in the question suggests OP wants to do that.

[shad0w_wa1k3r]

I just wanted to show another way of doing it while describing it's specific use. Partial answer.

[Dani]

Why would one need triple quotes AND backslash? Why not just backslash?

[Variadicism]

@AllDaniSpringer You could also do a single quoted string and it would work the same way; I just kept the triple quotes because that's what the question was asking about. I'll make an edit to mention that, though.