Missing comma between array elements
Two values in an array with only whitespace between them.
The input
[1 2][1, 2]How to fix it
Add a comma between the elements.
If you meant a single number, the space is the bug; `12` and `1 2` are different documents.
What each parser reports
Every message below was captured by running this exact input through the parser named. 21 of 21 parsers rejected it.
| Parser | Exact message |
|---|---|
| CPython json.loads CPython 3.12.3 | Expecting ',' delimiter: line 1 column 4 (char 3)what this message means → |
| encoding/json Unmarshal Go go1.22.2 | invalid character '2' after array elementwhat this message means → |
| Gson Java 21.0.12 | Unterminated array at line 1 column 5 path $[1]what this message means → |
| Gson JsonParser (lenient off) Java 21.0.12 | Unterminated array at line 1 column 5 path $[1]what this message means → |
| hjson Node.js 22.22.2 | End of input while parsing an array (missing ']') at line 1,5 >>>1 2] ...what this message means → |
| Jackson ObjectMapper Java 21.0.12 | Unexpected character ('2' (code 50)): was expecting comma to separate Array entrieswhat this message means → |
| JavaScriptCore JSON.parse JavaScriptCore (Bun 1.4.1) | JSON Parse error: Expected ']'what this message means → |
| json-bigint Node.js 22.22.2 | Expected ',' instead of '2'what this message means → |
| JSON5 Node.js 22.22.2 | JSON5: invalid character '2' at 1:4what this message means → |
| JSON::PP Perl 5.038002 | , or ] expected while parsing array, at character offset 3 (before "2]")what this message means → |
| json_decode PHP 8.3.6 | Syntax error |
| Newtonsoft.Json JsonConvert Newtonsoft.Json 13.0.3 on .NET 8.0.30 | After parsing a value an unexpected character was encountered: 2. Path '[0]', line 1, position 3.what this message means → |
| Newtonsoft.Json JsonTextReader Newtonsoft.Json 13.0.3 on .NET 8.0.30 | After parsing a value an unexpected character was encountered: 2. Path '[0]', line 1, position 3.what this message means → |
| orjson CPython 3.12.3 | unexpected character, expected ',' or ']': line 1 column 4 (char 3)what this message means → |
| Ruby JSON.parse Ruby 3.2.3 | unexpected token at '2]' |
| serde_json::from_str Rust (serde_json 1.x) | expected `,` or `]` at line 1 column 4what this message means → |
| SpiderMonkey JSON.parse SpiderMonkey 115 | JSON.parse: expected ',' or ']' after array element at line 1 column 4 of the JSON datawhat this message means → |
| System.Text.Json Deserialize .NET 8.0.30 | '2' is invalid after a value. Expected either ',', '}', or ']'. Path: $ | LineNumber: 0 | BytePositionInLine: 3.what this message means → |
| System.Text.Json JsonDocument .NET 8.0.30 | '2' is invalid after a value. Expected either ',', '}', or ']'. LineNumber: 0 | BytePositionInLine: 3.what this message means → |
| ujson CPython 3.12.3 | Unexpected character found when decoding array value (2)what this message means → |
| V8 JSON.parse Node.js 22.22.2 | Expected ',' or ']' after array element in JSON at position 3 (line 1 column 4)what this message means → |
What the specification says
The exact sections that govern this error. Descriptions are our paraphrase; follow the links for the normative text.
| Body | Section |
|---|---|
| IETF | An array is square brackets around zero or more values, with elements separated by commas. |
| Ecma International | Gives the array grammar; values are separated by commas. |
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