Elisp split-string function to split a string by . character

Question

I am trying to split a string using 'split-string' function based on the . character. But (split-string "1.2.3" ".") doesn't work at all. It just returns a list of variable number of empty strings. Is . a special character that needs to be escaped or specified in some different way?

Answer 1

Here is the official documentation for split-string function - https://www.gnu.org/software/emacs/manual/html_node/elisp/Creating-Strings.html

The second argument to the split-string function in (split-string "1.2.3" "\.") is a regular expression and as a result both the '.' character and '\' character have special meaning. So the '.' character needs to be escaped and even the '\' character needs to be escaped with another '\'. (split-string "1.2.3" "\\.") will work fine as expected.