### 5.1 Escape Sequences in String Constants

In double-quoted strings, the backslash character is used to introduce escape sequences that represent other characters. For example, ‘`\n`’ embeds a newline character in a double-quoted string and ‘`\"`’ embeds a double quote character. In single-quoted strings, backslash is not a special character. Here is an example showing the difference:

         toascii ("\n")
             ⇒ 10
         toascii ('\n')
             ⇒ [ 92 110 ]

Here is a table of all the escape sequences used in Octave (within double quoted strings). They are the same as those used in the C programming language.

`\\`
  Represents a literal backslash, ‘`\`’.
`\"`
  Represents a literal double-quote character, ‘`"`’.
`\'`
  Represents a literal single-quote character, ‘`'`’.
`\0`
  Represents the “nul” character, control-@, ASCII code 0.
`\a`
  Represents the “alert” character, control-g, ASCII code 7.
`\b`
  Represents a backspace, control-h, ASCII code 8.
`\f`
  Represents a formfeed, control-l, ASCII code 12.
`\n`
  Represents a newline, control-j, ASCII code 10.
`\r`
  Represents a carriage return, control-m, ASCII code 13.
`\t`
  Represents a horizontal tab, control-i, ASCII code 9.
`\v`
  Represents a vertical tab, control-k, ASCII code 11.

In a single-quoted string there is only one escape sequence: you may insert a single quote character using two single quote characters in succession. For example,

         'I can''t escape'
             ⇒ I can't escape

In scripts the two different string types can be distinguished if necessary by using `is_dq_string` and `is_sq_string`.

— Built-in Function: is_dq_string (x)

> Return true if x is a double-quoted character string.

> See also: is_sq_string, ischar.

— Built-in Function: is_sq_string (x)

> Return true if x is a single-quoted character string.

> See also: is_dq_string, ischar.