What is the difference between single and double quoted strings?

Question

What is the difference between single and double quoted strings?

Is there a way to get a variable expanded inside a string, or do they always need to be joined like: 'Hello, ' . s:name . '!'

Answer 1

The only difference between single and double quoted string is related to backslash. To display special characters like newline, bells, tabs, etc, you need to use double-quotes -> "\n".

Within a single-quoted string, '\' is itself => '\n' is a two-characters string (a backslash + n). Within double quotes, you have to double it -> "\\", which makes them un-practical to define regexes.

Regarding string expansion, you have a few choices:

• 'Hello, ' . s:name . '!'
• join(['Hello, ', s:name, '!'], '') -- which we never use
• printf('Hello %s!', s:name)
• lh#fmt#printf('Hello %1!', s:name) -- from lh-vim-lib, when we don't want to know about types, and when we don't need to format fields, but when we want to use formats like: 'Hello %1. How are you doing %1 this %2'.