Function read_checked

pub fn read_checked(value: &Json) -> Result<Found, String>

Reads a service response, refusing missing or wrongly typed answer fields.

A successful LRCLIB body carries a boolean instrumental and both lyric fields, each either a string or null. An empty but correctly typed answer is Found::Nothing; an error object is refused rather than counted as an ordinary miss. HTTP 404 must be handled by the caller before this parser.