How to replace forward slashes with backslashes in a string in Emacs Lisp?

Question

I would like to replace forward slashes with backslashes in emacs lisp. If I use this : ``` (replace-regexp-in-string "/" "\" path)) ``` I get an error. ``` (error "Invalid use of `\' in replacement text") ``` So how to represent the backslash in the second regexp?

Accepted Answer

What you are seeing in `"C:\foo\bar"` is the textual representation of the string `"C:\foo\bar"`, with escaped backslashes for further processing.

For example, if you make a string of length 1 with the backslash character:

```
(make-string 1 ?\)
```

you get the following response (e.g. in the minibuffer, when you evaluate the above with C-x C-e):

```
"\"
```

Another way to get what you want is to switch the "literal" flag on:

```
(replace-regexp-in-string "/" "\" path t t)
```

By the way, you don't need to escape the slash.

How to replace forward slashes with backslashes in a string in Emacs Lisp?

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