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json(3tcl) JSON json(3tcl) 





NAME


json - JSON parser






SYNOPSIS


package require Tcl 8.4


package require json ?1.3.4?


::json::json2dict txt


::json::many-json2dict txt ?max?










DESCRIPTION


The json package provides a simple Tcl-only library for
    parsing the JSON http://www.json.org/ data exchange format as
    specified in RFC 4627 http://www.ietf.org/rfc/rfc4627.txt. There is
    some ambiguity in parsing JSON because JSON has type information that is not
    maintained by the Tcl conversion. The json package returns data as a
    Tcl dict. Either the dict package or Tcl 8.5 is required for
    use.






COMMANDS



  
::json::json2dict txt

  
Parse JSON formatted text txt into a Tcl dict and return the value.
    
If txt contains more than one JSON entity only the
        first one is returned.

  

  
::json::many-json2dict txt ?max?

  
Parse JSON formatted text txt containing multiple JSON entities
      into a list of dictionaries and return that list.
    
If max is specified exactly that many entities are
        extracted from txt. By default the command will attempt to
        extract all, without limits. A value of "max == 0" does
        not make sense and will cause the command to throw an error.

  








EXAMPLES


An example of a JSON array converted to Tcl. A JSON array is
    returned as a single item with multiple elements.






[


    {


       "precision": "zip",


       "Latitude":  37.7668,


       "Longitude": -122.3959,


       "Address":   "",


       "City":      "SAN FRANCISCO",


       "State":     "CA",


       "Zip":       "94107",


       "Country":   "US"


    },


    {


       "precision": "zip",


       "Latitude":  37.371991,


       "Longitude": -122.026020,


       "Address":   "",


       "City":      "SUNNYVALE",


       "State":     "CA",


       "Zip":       "94085",


       "Country":   "US"


    }
]
=>
{Country US Latitude 37.7668 precision zip State CA City {SAN FRANCISCO} Address {} Zip 94107 Longitude -122.3959} {Country US Latitude 37.371991 precision zip State CA City SUNNYVALE Address {} Zip 94085 Longitude -122.026020}





An example of a JSON object converted to Tcl. A JSON object is
    returned as a multi-element list (a dict).






{


    "Image": {


        "Width":  800,


        "Height": 600,


        "Title":  "View from 15th Floor",


        "Thumbnail": {


            "Url":    "http://www.example.com/image/481989943",


            "Height": 125,


            "Width":  "100"


        },


        "IDs": [116, 943, 234, 38793]


    }
}
=>
Image {IDs {116 943 234 38793} Thumbnail {Width 100 Height 125 Url http://www.example.com/image/481989943} Width 800 Height 600 Title {View from 15th Floor}}









RELATED


To write json, instead of parsing it, see package
    json::write.






BUGS, IDEAS, FEEDBACK


This document, and the package it describes, will undoubtedly
    contain bugs and other problems. Please report such in the category
    json of the Tcllib Trackers
    [http://core.tcl.tk/tcllib/reportlist]. Please also report any ideas for
    enhancements you may have for either package and/or documentation.


When proposing code changes, please provide unified diffs,
    i.e the output of diff -u.


Note further that attachments are strongly preferred over
    inlined patches. Attachments can be made by going to the Edit form of
    the ticket immediately after its creation, and then using the left-most
    button in the secondary navigation bar.






KEYWORDS


data exchange, exchange format, javascript, json






CATEGORY


CGI programming






COPYRIGHT


Copyright (c) 2006 ActiveState Software Inc.
Copyright (c) 2009 Thomas Maeder, Glue Software Engineering AG








  

    1.3.4
    tcllib