70 lines
2.1 KiB
Plaintext
70 lines
2.1 KiB
Plaintext
[/
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/ Copyright (c) 2008 Marcin Kalicinski (kalita <at> poczta dot onet dot pl)
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/ Copyright (c) 2009 Sebastian Redl (sebastian dot redl <at> getdesigned dot at)
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/
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/ Distributed under the Boost Software License, Version 1.0. (See accompanying
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/ file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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/]
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[section JSON Parser]
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[def __json__ [@http://en.wikipedia.org/wiki/JSON JSON format]]
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The __json__ is a data interchange format derived from the object literal
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notation of JavaScript. (JSON stands for JavaScript Object Notation.)
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JSON is a simple, compact format for loosely structured node trees of any depth,
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very similar to the property tree dataset. It is less structured than XML and
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has no schema support, but has the advantage of being simpler, smaller and typed
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without the need for a complex schema.
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The property tree dataset is not typed, and does not support arrays as such.
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Thus, the following JSON / property tree mapping is used:
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* JSON objects are mapped to nodes. Each property is a child node.
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* JSON arrays are mapped to nodes. Each element is a child node with an empty
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name. If a node has both named and unnamed child nodes, it cannot be mapped
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to a JSON representation.
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* JSON values are mapped to nodes containing the value. However, all type
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information is lost; numbers, as well as the literals "null", "true" and
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"false" are simply mapped to their string form.
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* Property tree nodes containing both child nodes and data cannot be mapped.
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JSON round-trips, except for the type information loss.
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For example this JSON:
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{
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"menu":
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{
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"foo": true,
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"bar": "true",
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"value": 102.3E+06,
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"popup":
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[
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{"value": "New", "onclick": "CreateNewDoc()"},
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{"value": "Open", "onclick": "OpenDoc()"},
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]
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}
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}
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will be translated into the following property tree:
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menu
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{
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foo true
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bar true
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value 102.3E+06
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popup
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{
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""
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{
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value New
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onclick CreateNewDoc()
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}
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""
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{
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value Open
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onclick OpenDoc()
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}
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}
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}
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[endsect] [/json_parser]
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