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Ruby 1.8 String Literal

Delimiters:
  'singlequote'    "doublequote" 
  %q/single/       %Q!double!    
  %q<single>       %Q(double)    
                   %{double}     

Heredoc:

Following a << you can specify a string or an identifier to terminate the string
literal, and all lines following the current line up to the terminator are the
value of the string. If the terminator is quoted, the type of quotes determines
the type of the line-oriented string literal. Notice there must be no space
between << and the terminator.

If the - placed before the delimiter, then all leading whitespcae characters
(tabs or spaces) are stripped from input lines and the line containing
delimiter. This allows here-documents within scripts to be indented in a natural
fashion.

print <<EOF
The price is #{$Price}.
EOF

print <<"EOF";			# same as above
The price is #{$Price}.
EOF

print <<`EOC`			# execute commands
echo hi there
echo lo there
EOC

print <<"foo", <<"bar"	# you can stack them
I said foo.
foo
I said bar.
bar

myfunc(<<"THIS", 23, <<'THAT')
Here's a line
or two.
THIS
and here's another.
THAT

Escapes (double-quote):

|----+-----+---------------------+------+-----|
| E  | ASC | Name(s)             |  Hex | Dec |
|----+-----+---------------------+------+-----|
| \a | BEL | bell, alert         | 0x07 |   7 |
| \b | BS  | backspace           | 0x08 |   8 |
| \e | ESC | escape              | 0x1b |  27 |
| \f | NP  | formfeed, newpage   | 0x0c |  12 |
| \n | NL  | linefeed, newline   | 0x0a |  10 |
| \r | CR  | carriage return     | 0x0d |  13 |
| \s | SP  | space               | 0x20 |  32 |
| \t | HT  | tab, horizontal tab | 0x09 |   9 |
| \v | VT  | vertical tab        | 0x0b |  11 |
|----+-----+---------------------+------+-----|

|---------+------------------|
| Format  | Translation      |
|---------+------------------|
| \nnn    | Octal nnn        |
| \xnn    | Hexadecimal 0xnn |
| \cx     | Control-x        |   Control-x == (?x & 0b10011111)
| \C-x    | Control-x        |
| \M-x    | Meta-x           |   Meta-x == (?x | 0b10000000)
| \M-\C-x | Meta-control-x   | 
| \x      | x                |
| #{expr} | Value of expr    |
|---------+------------------|

Escapes (single-quote)

|----+-----+--------------+------+-----|
| E  | ASC | Name         |  Hex | Dec |
|----+-----+--------------+------+-----|
| \' | '   | single-quote | 0x27 |  39 |
| \\ | \   | backslash    | 0x5c |  92 |
|----+-----+--------------+------+-----|