fjordtools / Errors
Error explainers
What common error messages mean, why they happen and how to fix them, with examples you can check in your browser.
Data
6 explainers- Unexpected token < in JSON at position 0The response starts with <, so it is HTML or XML, not JSON.
- Unexpected end of JSON inputThe JSON text is empty or ends where more was expected.
- Unexpected token } in JSON (trailing comma)A comma before } or ] is not allowed in JSON.
- Unexpected token u in JSON at position 0JSON.parse got the value undefined, which turned into the text "undefined".
- Unexpected token ' in JSON at position 1JSON needs double quotes. Single quotes, as in Python or JavaScript, are rejected.
- Unexpected non-whitespace character after JSON at position 8There is more text after the first complete JSON value.
Convert
3 explainers- InvalidCharacterError: The string to be decoded is not correctly encodedatob() rejects anything outside the standard Base64 alphabet.
- Invalid Datenew Date(...) could not read the text, so the date is NaN.
- mapping values are not allowed hereA colon in the wrong place: a second key on the same line, or a value that needs quotes.
Security
3 explainersDevOps
1 explainerText
3 explainers- SyntaxError: Invalid regular expression: Nothing to repeatA quantifier such as * or + has nothing in front of it to repeat.
- SyntaxError: Invalid regular expression: Unterminated groupA ( has no matching ), so the pattern ends inside a group.
- SyntaxError: Invalid regular expression: Invalid groupA (? group uses syntax that JavaScript does not have.
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