Enum TraceParseError 

#[non_exhaustive]
pub enum TraceParseError {
    LineTooLong {
        line: usize,
        length: usize,
        limit: usize,
    },
    TooManyEvents {
        limit: usize,
    },
    BlankLine {
        line: usize,
    },
    Malformed {
        line: usize,
        source: Error,
    },
    ByteOrderMark,
    NotJsonLines {
        array: bool,
    },
    NonMonotonicSeq {
        line: usize,
        seq: u64,
        previous: u64,
    },
}

Why a trace document was rejected. Every variant that addresses one record carries its 1-based line number; the two that describe the document as a whole do not.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

LineTooLong

A line exceeded Limits::max_line_bytes.

Fields

line: usize

1-based line number.

length: usize

Observed length in bytes.

limit: usize

The configured cap.

TooManyEvents

The document contains more than Limits::max_events events.

Fields

limit: usize

The configured cap.

BlankLine

A line was empty (JSON Lines forbids blank records; a single trailing newline is fine).

Fields

line: usize

1-based line number.

Malformed

A line was not a valid TraceEvent object.

Fields

line: usize

1-based line number.

source: Error

The underlying JSON error.

ByteOrderMark

The document begins with a UTF-8 byte-order mark.

Its own variant because serde reports it as expected value at line 1 column 1, which is true and tells the reader nothing: the offending bytes are invisible in every editor that wrote them. A BOM is the commonest way a trace produced on Windows fails to parse — Out-File and Set-Content have both emitted one by default — and jq, python -m json.tool and every other tool the reader might reach for will insist the file is fine.

NotJsonLines

The whole document is a single JSON value: it is JSON, not JSON Lines.

Checked only after a line has already failed, so a valid document never reaches it and the cost is paid once, on the error path. Pretty-printing is the other half of the same mistake as the BOM — a file that is obviously well-formed JSON, rejected with a message about column 1.

Fields

array: bool

Whether that value is an array, so the message can name the fix.

NonMonotonicSeq

Event seq values must be strictly increasing in document order.

Fields

line: usize

1-based line number.

seq: u64

The seq on this line.

previous: u64

The seq on the previous event line.

Trait Implementations

impl Debug for TraceParseError

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for TraceParseError

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Error for TraceParseError

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0:

use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.