Ion

/* A comment
*/

// A comment

null.sexp         // A null S-expression value
()                // An empty expression value
(cons 1 2)        // S-expression of three values
([hello][there])  // S-expression containing two lists

(a+-b)  ( 'a' '+-' 'b' )    // Equivalent; three symbols
(a.b;)  ( 'a' '.' 'b' ';')  // Equivalent; four symbols

null.list         // A null list value
[]                // An empty list value
[1, 2, 3]         // List of three ints
[ 1 , two ]       // List of an int and a symbol
[a , [b]]         // Nested list
[ 1.2, ]          // Trailing comma is legal in Ion (unlike JSON)
[ 1, , 2 ]        // ERROR: missing element between commas

int32::12                                // Suggests 32 bits as end-user type
'my.custom.type' :: { x : 12 , y : -1 }  // Gives a struct a user-defined type

{ field: something::'another thing'::value }  // Field's name must precede annotations of its value

jpeg :: {{ ... }}                        // Indicates the blob contains jpeg data
bool :: null.int                         // A very misleading annotation on the integer null
'' :: 1                                  // An empty annotation
null.symbol :: 1                         // ERROR: type annotation cannot be null

myvar2       // A different symbol
'hi ho'      // Symbol requiring quotes

null.decimal      // A null decimal value
0.123             // Type is decimal
-0.12d4           // Type is decimal
123_456.789_012   // Decimal with underscores
-0d-1             // Decimal maintains precision: -0. != -0.0
-0d0              // Negative zero decimal (distinct from positive zero)

// Timestamps represent a specific moment in time, always include a local offset, and are capable of arbitrary precision.
2007-02-23T12:14Z                // Seconds are optional, but local offset is not
2007-01-01T00:00-00:00           // Happy New Year in UTC, unknown local offset

// The clob type is similar to blob in that it holds uninterpreted binary data. The difference is that the content is expected to be text, so we use a text notation that’s more readable than Base64.
// An Ion clob type is similar to the blob type except that the denotation in the Ion text format uses an ASCII-based string notation rather than a base64 encoding to denote its binary value. It is important to make the distinction that clob is a sequence of raw octets and string is a sequence of Unicode code points.
// The string may only contain legal 7-bit ASCII character

// In the text format, blob values are denoted as RFC 4648-compliant Base64 text within two pairs of curly braces.
// A valid blob value with one required padding character.
{{ VG8gaW5maW5pdHkuLi4gYW5kIGJleW9uZCE= }}

"hello world"

null

( '''hello '''     // Sexp with one element
  '''world!'''  )

("hello world!")   // The exact same sexp value

// This Ion value is a string containing three newlines. The serialized
// form's first newline is escaped into nothingness.
'''\
The first line of the string.
This is the second line of the string,
and this is the third line.
'''

// http://amzn.github.io/ion-docs/docs/spec.html
null.int   // A null int value
0          // Zero.  Surprise!
-0         //   ...the same value with a minus sign
123        // A normal int
-123       // Another negative int
0xBeef     // An int denoted in hexadecimal
0b0101     // An int denoted in binary
1_2_3      // An int with underscores
0xFA_CE    // An int denoted in hexadecimal with underscores
0b10_10_10 // An int denoted in binary with underscores

// A subset of symbols called identifiers can be denoted in text without single-quotes.

// http://amzn.github.io/ion-docs/docs/spec.html
-0.12e4           // Type is float

{ first : "Tom" , last: "Riddle" }  // Structure with two fields
{"first":"Tom","last":"Riddle"}     // The same value with confusing style
{center:{x:1.0, y:12.5}, radius:3}  // Nested struct

null.bool
true
false