Dot notation with single quotes

Setup

Selector: $.'key'

{
  "key": "value",
  "'key'": 42
}

Results

Other responses

Bash (JSONPath.sh) 

[
  "value"
]

C (json-glib) 

[
  42
]

Clojure (json-path) ¹ 

"value"

Cpp (jsoncons) 

[
  "value"
]

Dart (json_path)

Not supported

ParserException[1:2]: end of input expected

Elixir (ExJsonPath)

Not supported

syntax error before: {string,1,<<"key">>}

Elixir (jaxon) 

[
  42
]

Elixir (warpath) ¹

Not supported

Parser error: Invalid token on line 1, syntax error before: <<"key">>

FSharp (FSharp.Data.JsonPath) 

[
  42
]

Golang (github.com-PaesslerAG-jsonpath) ¹

Not supported

parsing error: $.'key'	:1:3 - 1:8 unexpected Char while scanning JSON select expected Ident, "." or "*"

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

"value"

Golang (github.com-ohler55-ojg)

Not supported

Golang (github.com-oliveagle-jsonpath) ¹ 

42

Golang (github.com-spyzhov-ajson) 

[
  "value"
]

Golang (github.com-theory-jsonpath)

Not supported

jsonpath: unexpected string at position 3

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

[
  42
]

Haskell (jsonpath)

Not supported

Invalid JSONPath: $.'key'
 Error: 1:3:
  |
1 | $.'key'
  |   ^
unexpected '''
expecting '.' or white space

JavaScript (Goessner) ² 

[
  "value"
]

JavaScript (brunerd)

Not supported

JavaScript (jsonpath)

Not supported

Parse error on line 1:
$.'key'
--^
Expecting 'STAR', 'IDENTIFIER', 'SCRIPT_EXPRESSION', 'INTEGER', 'END', got 'Q_STRING'

JavaScript (jsonpath-plus) 

[
  "value"
]

JavaScript (jsonpathly)

Not supported

mismatched input ''key'' expecting {'*', 'true', 'false', 'null', KEY, SPECIAL_KEY, NUMBER}

Java (com.github.jsurfer)

Not supported

line 1:2 no viable alternative at input '.'key''
org.antlr.v4.runtime.misc.ParseCancellationException

Java (com.github.xmljacquard.ajp)

Not supported

Error at char 18 in expression in xsl:sequence/@select on line 20 column 67 of ajp-runner.xslt:
   <failed xmlns:ixml="http://invisiblexml.org/NS"
  ixml:state="failed"><line>1</line><column>3</column><pos>3</pos><unexpected>'</unexpected><permitted>'*', '_', [#80-'퟿[xd7ff]'], ['A'-'Z'; 'a'-'z'], ['𐀀[x10000]'-'􏿯[x10ffef]'], ['[xe000]'-'￯[xffef]']</permitted><could-be-next><in rule="ALPHA"><tokens>['A'-'Z'; 'a'-'z']</tokens></in><in rule="wildcard-selector"><tokens>'*'</tokens></in><in rule="name-first"><tokens>'_', [#80-'퟿[xd7ff]'], ['𐀀[x10000]'-'􏿯[x10ffef]'], ['[xe000]'-'￯[xffef]']</tokens></in></could-be-next><unfinished><open rule="child-segment" start="2" end="2"><input>.</input></open><open rule="jsonpath-query" start="1" end="1"><input>$</input></open></unfinished></failed>
During lazy evaluation of tailCallLoop(ajp:getProcessor(...)) on line 20 of jar:file:./implementations/Java_com.github.xmljacquard.ajp/build/deps/org/xmljacquard/ajp/0.0.7/ajp-0.0.7.jar!/xslt/ajp-runner.xslt
In function ajpr:getProcessor on line 17 column 106 of ajp-runner.xslt:
net.sf.saxon.s9api.SaxonApiException: <failed xmlns:ixml="http://invisiblexml.org/NS" ixml:state="failed"><line>1</line><column>3</column><pos>3</pos><unexpected>'</unexpected><permitted>'*', '_', [#80-'퟿'], ['A'-'Z'; 'a'-'z'], ['𐀀'-'􏿯'], [''-'￯']</permitted><could-be-next><in rule="ALPHA"><tokens>['A'-'Z'; 'a'-'z']</tokens></in><in rule="wildcard-selector"><tokens>'*'</tokens></in><in rule="name-first"><tokens>'_', [#80-'퟿'], ['𐀀'-'􏿯'], [''-'￯']</tokens></in></could-be-next><unfinished><open rule="child-segment" start="2" end="2"><input>.</input></open><open rule="jsonpath-query" start="1" end="1"><input>$</input></open></unfinished></failed>

Java (com.jayway.jsonpath) ¹ ³ 

42

Kotlin (com.nfeld.jsonpathkt) ¹ 

42

Objective-C (SMJJSONPath) ¹ ³ 

42

PHP (Goessner) ² 

[
  "value"
]

PHP (galbar-jsonpath)

Not supported

Invalid JSONPath error: 'Error in JSONPath near '.'key'''

PHP (remorhaz-jsonpath) 

[
  "value"
]

PHP (softcreatr-jsonpath) 

[
  "value"
]

Perl (JSON-Path) 

[
  "value"
]

Python (jsonpath) ² 

[
  "value"
]

Python (jsonpath-ng) 

[
  "value"
]

Python (jsonpath-rw) 

[
  "value"
]

Python (jsonpath2)

Not supported

line 1:2 token recognition error at: '''
ValueError("line 1:2 token recognition error at: '''")

Python (python-jsonpath)

Not supported

JSONPathSyntaxError('expected a shorthand selector')

Raku (JSON-Path)

Not supported

JSON path parse error at position 1

Ruby (janeway-jsonpath)

Not supported

Jsonpath query $.'key' - Dot "." begins a name selector, and must be followed by an object member name, "'key'" is invalid here

Ruby (jsonpath) 

[
  "value"
]

Rust (jsonpath)

Not supported

parsing error

Rust (jsonpath_lib)

Not supported

path error: 
$.'key'
^^

Rust (serde_json_path)

Not supported

at position 2, in dot member name, must start with lowercase alpha or '_'

Scala (jsonpath) 

[
  42
]

Swift (Sextant) 

[
  42
]

dotNET (Json.NET) 

[
  42
]

dotNET (JsonCons.JsonPath) 

[
  "value"
]

dotNET (JsonPath.Net)

Not supported

Could not find any valid selectors.

dotNET (JsonPathLib) 

[
  "value"
]

dotNET (Manatee.Json) 

[
  "value"
]

Errors

Erlang (ejsonpath) 

init terminating in do_boot (function_clause)

Crash dump is being written to: /dev/null...done
{"init terminating in do_boot",function_clause}

JavaScript (json-p3) 

unexpected shorthand selector ''' ('$.'key'':2)

Rust (jsonpath_plus) 

Error Parsing JSON Path:
$.'key'
panic occurred

Footnotes