ruby - Backslashes in single quoted strings vs. double quoted strings

Question

If I add a backslash+space to the start of double and single quoted strings, I get different results:

" text"
' text' 

In the output for the double quoted string I see only a space.
In the output for the single quoted string I see backslash+space.

What's happening there? Is this because ' ' is interpreted as a special character in the double quote string but in the single quoted string the characters are preserved as is?

If I change the strings to this, I see the same output, namely a single slash followed by a space and then the text:

"\ text"
'\ text' 

In both cases the backslash is escaped. I'm confused why they work the same way in this situation.

Is there some rule that would help to explain the fundamental difference between how single quoted strings and double quoted strings handle backslashes in Ruby?

Answer 1

Double-quoted strings support the full range of escape sequences, as shown below:

• a Bell/alert (0x07)
• Backspace (0x08)
• e Escape (0x1b)
• f Formford (0x0c)
• Newline (0x0a)
• Return (0x0d)
• s Space (0x20)
• Tab (0x09)
• v Vertical tab (0x0b)

For single-quoted strings, two consecutive backslashes are replaced by a single backslash, and a backslash followed by a single quote becomes a single quote:

'escape using ""' -> escape using ""
'That's right'     -> That's right