Filter expression on object

Setup

Selector: $[?(@.key)]

{"key": 42, "another": {"key": 1}}

Results

Other responses

Bash (JSONPath.sh) 

[]

C (json-glib)

Not supported

Unable to compile selector `$[?(@.key)]': Invalid array index definition “?(@.key)]”

Clojure (json-path) ¹ 

[
  {
    "key": 1
  }
]

Cpp (jsoncons) 

[
  {
    "key": 1
  }
]

Dart (json_path) 

[
  {
    "key": 1
  }
]

Elixir (ExJsonPath)

Not supported

syntax error before: ')'

Elixir (jaxon) 

[]

Elixir (warpath) ¹ 

[
  {
    "another": {
      "key": 1
    },
    "key": 42
  }
]

Erlang (ejsonpath) 

[
  {
    "key": 1
  }
]

Golang (github.com-AsaiYusuke-jsonpath) ² 

[
  {
    "key": 1
  }
]

Golang (github.com-PaesslerAG-jsonpath) ¹ 

[
  {
    "key": 1
  }
]

Golang (github.com-bhmj-jsonslice) ¹ ³ 

[]

Golang (github.com-ohler55-ojg)

Not supported

Golang (github.com-spyzhov-ajson) 

[
  {
    "key": 1
  }
]

Golang (github.com-vmware-labs-yaml-jsonpath) 

[
  {
    "another": {
      "key": 1
    },
    "key": 42
  }
]

Haskell (jsonpath) 

[
  {
    "key": 1
  }
]

JavaScript (Goessner) ² 

[
  42,
  {
    "key": 1
  }
]

JavaScript (brunerd) 

[
  42,
  {
    "key": 1
  }
]

JavaScript (jsonpath) 

[
  {
    "key": 1
  }
]

JavaScript (jsonpath-plus) 

[
  {
    "key": 1
  }
]

Java (com.github.jsurfer) 

[
  {
    "key": 1
  }
]

Java (com.jayway.jsonpath) ¹ ³ 

[
  {
    "another": {
      "key": 1
    },
    "key": 42
  }
]

Kotlin (com.nfeld.jsonpathkt) ¹

Not supported

Unexpected char, char=?, index=2

Objective-C (SMJJSONPath) ¹ ³ 

[
  {
    "another": {
      "key": 1
    },
    "key": 42
  }
]

PHP (galbar-jsonpath) ² 

[
  {
    "key": 1
  }
]

PHP (remorhaz-jsonpath) 

[
  {
    "another": {
      "key": 1
    },
    "key": 42
  }
]

PHP (softcreatr-jsonpath) 

[
  {
    "key": 1
  }
]

Python (jsonpath) ² 

[
  {
    "key": 1
  }
]

Python (jsonpath-ng)

Not supported

JsonPathLexerError('Error on line 1, col 2: Unexpected character: ? ')

Python (jsonpath-rw)

Not supported

JsonPathLexerError('Error on line 1, col 2: Unexpected character: ? ')

Python (jsonpath2) 

[
  {
    "another": {
      "key": 1
    },
    "key": 42
  }
]

Raku (JSON-Path)

Not supported

Evaluation of embedded Perl 6 code not allowed (construct with :allow-eval)

Ruby (jsonpath) 

[
  {
    "another": {
      "key": 1
    },
    "key": 42
  }
]

Rust (jsonpath)

Not supported

parsing error

Rust (jsonpath_lib) 

[
  {
    "another": {
      "key": 1
    },
    "key": 42
  }
]

Rust (jsonpath_plus) 

[]

Scala (jsonpath) 

[
  {
    "another": {
      "key": 1
    },
    "key": 42
  }
]

Swift (Sextant) 

[
  {
    "another": {
      "key": 1
    },
    "key": 42
  }
]

dotNET (Json.NET) 

[]

dotNET (JsonCons.JsonPath) 

[
  {
    "key": 1
  }
]

dotNET (JsonPath.Net) 

[
  {
    "key": 1
  }
]

dotNET (JsonPathLib) 

[
  {
    "key": 1
  }
]

dotNET (Manatee.Json) 

[
  {
    "key": 1
  }
]

JSON (Path_Reference_Implementation)

Not supported

 --> 1:3
  |
1 | $[?(@.key)]
  |   ^---
  |
  = expected unionChild, unionArrayIndex, or sliceStart

Proposal (A) 

[
  {
    "key": 1
  }
]

Errors

Golang (github.com-oliveagle-jsonpath) ¹ 

key error:  not found in object

PHP (Goessner) ² 

ArgumentCountError

Perl (JSON-Path) 

non-safe evaluation, died at main.pl line 11.

Footnotes