This library can be used to parse and serialize (encode/decode) JSON strings in pure PicoLisp.
NEW: Please read EXPLAIN_v3.md to learn more about PicoLisp and this (v3
) JSON library.
Please read EXPLAIN.md to learn more about PicoLisp and the older (v2
) JSON library.
- PicoLisp 32-bit
v3.1.11
tov20.6
(tested) - PicoLisp 64-bit
v17.12
tov20.6
(tested) - PicoLisp 64-bit
pil21
(tested)
BREAKING CHANGE since v4.0.0: Namespaces have been completely removed, and all function names are now prefixed with json- (see Changelog).
This library has been rewritten in pure PicoLisp and contains no external dependencies.
These FFI bindings require the Parson C library, compiled as a shared library
- Include
json.l
in your project - Try the examples below
Public functions:
(json-decode arg1 arg2)
parses a JSON string or filearg1
String: the JSON string or filename you want to decodearg2
Flag (optional): a flag (T
orNIL
) indicating to parse a file if set
(json-encode arg1)
serializes a list into a JSON stringarg1
List: a PicoLisp list which will be converted to a JSON string
JSON | PicoLisp | Example |
---|---|---|
Number | Number | 25 <-> 25 |
String | String | "hello" <-> "hello" |
Null | Transient null Symbol | null <-> 'null |
Boolean | Transient true or false Symbol | true <-> 'true |
Array | List with T in cdar | {"array":[1,2,3]} <-> '(("array" T 1 2 3)) |
Object | Cons pair | {"hello":"world"} <-> '(("hello" . "world")) |
- To disallow duplicate Object keys:
(on *Json_prevent_duplicate_keys)
. Default allows duplicate Object keys. - A successful result will return a list.
- Failures return
NIL
, store the error message in*Msg
, and print the error message toSTDERR
(standard error). - Keys are in
car
, values are incdr
. - When the 2nd item in the list is
T
, the rest of the list represents a JSON array. - When the 2nd item in the list is a cons pair, it represents a JSON object.
- Supports Unicode characters as
"\uNNNN"
whereN
is a hexadecimal digit.
This library conforms to the ECMA-404 The JSON Data Interchange Standard, except for the following semantic exceptions:
- [Numbers] Scientific (floating point, fractional, exponential) numbers (ex:
3.7e-5
) are not accepted. They must be provided as strings (ex:"3.7e-5"
).
(load "json.l")
(json-decode "{\"Hello\":\"World\"}")
-> (("Hello" . "World"))
The same function is used for parsing JSON strings and files.
Simply append T
as the last argument if you want to parse a file.
(load "json.l")
(json-decode "test.json" T)
-> (("first" . "John")
("last" . "Doe")
("age" . 25)
("registered" . true)
("interests" T "Reading" "Mountain Biking")
("favorites" ("color" . "blue") ("sport" . "running"))
("utf string" . "lorem ipsum")
("utf-8 string" . "あいうえお")
("surrogate string" . "lorem�ipsum�lorem") )
(load "json.l")
(json-encode '(("Hello" . "World")))
-> "{\"Hello\":\"World\"}"
(json-decode "{\"Hello\":invalid}")
"Invalid Object 'invalid', must be '[' OR '{' OR string OR number OR true OR false OR null"
-> NIL
This library comes with full unit tests. To run the tests, type:
make check
The following are alternatives also written in pure PicoLisp. They are limited by pipe/read syscalls.
- JSON reader/writer by Alexander Burger.
- JSON reader/writer by Henrik Sarvell.
If you find any bugs or issues, please create an issue.
If you want to improve this library, please make a pull-request.
Copyright (c) 2015-2020 Alexander Williams, Unscramble license@unscramble.jp