Questions tagged [backslash]

The backslash character \ (not to be confused with slash /) is used in many languages as an escape character to modify the meaning of the following character. It is also the directory separator in file paths under DOS and Windows.

The backslash character \ is a mirror version of the slash character /, created for use in computing. Its meaning depends on the context.

  • In many languages, \ followed by a character that has a special meaning makes the next character lose its special meaning. This is especially true inside string literals and regular expressions : for example, in many languages, "a\\b\"" represents the 4-character string a\b".
  • Sometimes \ gives the next character a special meaning. This is mostly the case when \ is followed by a letter or digit in a string literal, where it can be used to specify a control character or other special character. For example, \n specifies a newline in many languages, and \123 often specifies the character whose octal value is 123 (but note that some languages have different rules).
  • In DOS and Windows , the \ character is the directory (folder) separator in file paths. For example, c:\windows\cmd.exe is the file called cmd.exe in the directory called windows at the root of the c: drive.
  • In (La)TeX , \ starts a command name.
  • In Haskell , \ introduces a lambda expression .
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Difference between forward slash (/) and backslash (\) in file path

I was wondering about the difference between \ and / in file paths. I have noticed that sometimes a path contains /and sometimes it is with \. It would be great if anyone can explain when to use \ and /.
Spider man
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String.replaceAll single backslashes with double backslashes

I'm trying to convert the String \something\ into the String \\something\\ using replaceAll, but I keep getting all kinds of errors. I thought this was the solution: theString.replaceAll("\\", "\\\\"); But this gives the below exception:…
Frank Groeneveld
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How can I print a single backslash?

When I write print('\') or print("\") or print("'\'"), Python doesn't print the backslash \ symbol. Instead it errors for the first two and prints '' for the third. What should I do to print a backslash? This question is about producing a string…
Michael
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File path issues in R using Windows ("Hex digits in character string" error)

I run R on Windows, and have a csv file on the Desktop. I load it as follows, x<-read.csv("C:\Users\surfcat\Desktop\2006_dissimilarity.csv",header=TRUE) but the R gives the following error message Error: '\U' used without hex digits in character…
user297850
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Why do backslashes appear twice?

When I create a string containing backslashes, they get duplicated: >>> my_string = "why\does\it\happen?" >>> my_string 'why\\does\\it\\happen?' Why?
Zero Piraeus
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Escaping Strings in JavaScript

Does JavaScript have a built-in function like PHP's addslashes (or addcslashes) function to add backslashes to characters that need escaping in a string? For example, this: This is a demo string with 'single-quotes' and "double-quotes". ...would…
Steve Harrison
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So what IS the right direction of the path's slash (/ or \) under Windows?

It seems Windows insists on writing a backslash \ in file paths, whereas .NET's URI class writes them with a slash /. Is there any right way, that is accepted even in the most primitive systems? And why is .NET's URI showing the other slash…
Letterman
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Is there a way to put comments in multiline code?

This doesn't work: something = \ line_of_code * \ # Comment another_line_of_code * \ # Comment and_another_one * \ # Comment etc Neither does this: something = \ # Comment \ line_of_code * \ # Comment…
MarcinKonowalczyk
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Why are the backslash and semicolon required with the find command's -exec option?

I have begun to combine different commands in the linux terminal. I am wondering why the backslash and semicolon are required for a command such as: find ./ -name 'blabla' -exec cp {} ./test \; when a simple cp command is simply: cp randomfile…
wesk
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python replace single backslash with double backslash

In python, I am trying to replace a single backslash ("\") with a double backslash("\"). I have the following code: directory = string.replace("C:\Users\Josh\Desktop\20130216", "\", "\\") However, this gives an error message saying it doesn't like…
Josh Wood
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How can I use backslashes (\) in a string?

I tried many ways to get a single backslash from an executed (I don't mean an input from html). I can get special characters as tab, new line and many others then escape them to \\t or \\n or \\(someother character) but I cannot get a single…
Mik
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Javascript and backslashes replace

here is my string: var str = "This is my \string"; This is my code: var replaced = str.replace("/\\/", "\\\\"); I can't get my output to be: "This is my \\string" I have tried every combination I can think of for the regular expression and the…
Frankie
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How to replace a double backslash with a single backslash in python?

I have a string. In that string are double backslashes. I want to replace the double backslashes with single backslashes, so that unicode char codes can be parsed correctly. (Pdb) p fetched_page '

zzz
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How to remove backslash on json_encode() function?

How to remove the (\)backslash on a string? when using echo json_encode() ? For example: This is a test!

\")"; echo json_encode($str); ?> note: When you echo $str, there will be no problem... but when…
Ryan
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Replace "\\" with "\" in a string in C#

I still don't get how to do this. I saw many posts regarding this, but none of the solutions worked for me. I have a string called "a\\b". The result I need is "a\b". How is this done? I have a text file which has a database connection string…
Sandeep
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