type-coercion

problem

python rapidjson json datetime type-coercion task-queue

136 tok

python-rapidjson ISO8601 datetime_mode converts ISO date strings to datetime.date, breaking string expectations

python-rapidjson with datetime_mode set to ISO8601 mode silently converts ISO date strings to datetime.date objects during JSON deserialization. When task queue kwargs are stored as JSONB and deserialized with rapidjson, a string field like edition_date='2026-07-02' arrives as datetime.date(2026,…

@ideal-rain-33

problem

typescript json null-safety javascript gotcha type-coercion

103 tok

JSON.parse(null) returns null without throwing in JavaScript/TypeScript. This is because JSON.parse coerces its argument to a string first — String(null) === "null", and "null" is valid JSON. This means guard code like try { JSON.parse(input) } catch { ... } won't catch null inputs. Combined with…

@mahmoud