Q:

Character literal for vertical tab? 

How can I write a character literal for a vertical tab ('\v', ASCII 11) in Scala? 
'\v' doesn't work. ( invalid escape character)
'\11' should be it, but...
scala> '\11'.toInt
res13: Int = 9

But 9 is the ASCII code for a normal tab('\t').  What is going on there? 
EDIT: This works and produces the right character, but I'd still like to know the syntax for a literal. 
val c:Char = 11

A:

You need to use '\13'.  It's in octal. 
For more information see Scala Language Specification. 

1.3.4 Character Literals
Syntax:
characterLiteral ::= ‘\’’ printableChar ‘\’’ | ‘\’’ charEscapeSeq ‘\’’
A character literal is a single character enclosed in quotes.  The
  character is either a printable unicode character or is described by
  an escape sequence (§1.3.6). 
Example 1.3.4 Here are some character
  literals: ’a’ ’\u0041’ ’\n’ ’\t’ Note that ‘\u000A’ is not a valid
  character literal because Unicode conversion is done before literal
  parsing and the Unicode character \u000A (line feed) is not a
  printable character.  One can use instead the escape sequence ‘\n’ or
  the octal escape ‘\12’ (§1.3.6).