ref: ee695eff4329234e20abb68ff3100d3b15929418
dir: /man/6/json/
.TH JSON 6
.SH NAME
json \- javascript object notation
.SH DESCRIPTION
.I JSON
is a textual data transport encoding for a small collection of basic and structured values:
.BR null ,
booleans, numbers, strings, arrays, and objects (property/value list).
It is a subset of JavaScript (ECMAScript).
.IR Json (2)
describes a Limbo module that can read and write streams of JSON-encoded data.
.PP
The encoding syntax and its interpretation is defined by Internet RFC4627, but is briefly summarised here:
.IP
.EX
.ft R
.ta \w'\f2simple-xxx\f1'u +\w'\ ::=\ 'u
\f2text\fP ::= \f2array\fP | \f2object\fP
\f2value\fP ::= \f5null\fP | \f5true\fP | \f5false\fP | \f2number\fP | \f2string\fP | \f2array\fP | \f2object\fP
\f2object\fP ::= \f5'{'\fP [\f2pair\fP (\f5','\fP \f2pair\fP)*] \f5'}'\fP
\f2pair\fP ::= \f2string\fP \f5':'\fP \f2value\fP
\f2array\fP ::= \f5'['\fP [\f2value\fP (\f5','\fP \f2value\fP)*] \f5']'\fP
\f2number\fP ::= \f2int\fP \f2frac\fP? \f2exp\fP?
\f2int\fP ::= \f5'-'\fP? \f5[0-9]\fP | \f5[1-9][0-9]\fP+
\f2frac\fP ::= \f5'.'\fP \f5[0-9]\fP+
\f2exp\fP ::= \f5[eE][-+]\fP? \f5[0-9]\fP+
\f2string\fP ::= \f5'"'\fP \f2char\fP* \f5'"'\fP
\f2char\fP ::= \f5[^\ex00-\ex1F"\e\e]\fP |
\f5'\e"'\fP | \f5'\e/'\fP | \f5'\eb'\fP | \f5'\ef'\fP | \f5'\en'\fP | \f5'\er'\fP | \f5'\et'\fP |
\f5'\eu'\fP \f2hex\fP \f2hex\fP \f2hex\fP \f2hex\fP
\f2hex\fP ::= \f5[0-9a-fA-F]\fP
.EE
.PD
.DT
.PP
A sequence of blank, tab, newline or carriage-return characters (`white space') can appear
before or after opening and closing brackets and braces, colons and commas,
and is ignored.
The
.B null
represents a null value of any type.
The
.I strings
in the
.I pairs
of an
.I object
are intended to represent member names, and should be unique within that object.
Note that array and object denotations can be empty.
Also note that the RFC wants applications to exchange a
.I text
(ie, object or array) not an arbitrary
.IR value .
.SH SEE ALSO
.IR json (2),
.IR sexprs (6),
.IR ubfa (6)
.br
.br
D Crockford, ``The application/json Media Type for JavaScript Object Notation (JSON)'',
.IR RFC4627 .
.br
.B "http://www.json.org/"