Struct serde_json::Error

source · [−]

pub struct Error { /* private fields */ }

Expand description

This type represents all possible errors that can occur when serializing or deserializing JSON data.

Implementations

source

impl Error

source

pub fn line(&self) -> usize

One-based line number at which the error was detected.

Characters in the first line of the input (before the first newline character) are in line 1.

source

pub fn column(&self) -> usize

One-based column number at which the error was detected.

The first character in the input and any characters immediately following a newline character are in column 1.

Note that errors may occur in column 0, for example if a read from an IO stream fails immediately following a previously read newline character.

source

pub fn classify(&self) -> Category

Categorizes the cause of this error.

Category::Io - failure to read or write bytes on an IO stream
Category::Syntax - input that is not syntactically valid JSON
Category::Data - input data that is semantically incorrect
Category::Eof - unexpected end of the input data

source

pub fn is_io(&self) -> bool

Returns true if this error was caused by a failure to read or write bytes on an IO stream.

source

pub fn is_syntax(&self) -> bool

Returns true if this error was caused by input that was not syntactically valid JSON.

source

pub fn is_data(&self) -> bool

Returns true if this error was caused by input data that was semantically incorrect.

For example, JSON containing a number is semantically incorrect when the type being deserialized into holds a String.

source

pub fn is_eof(&self) -> bool

Returns true if this error was caused by prematurely reaching the end of the input data.

Callers that process streaming input may be interested in retrying the deserialization once more data is available.

Trait Implementations

source

impl Debug for Error

source

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

Formats the value using the given formatter. Read more

source

impl Display for Error

source

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

Formats the value using the given formatter. Read more

source

impl Error for Error

source

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

The lower-level source of this error, if any. Read more

1.0.0 · source

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

source

fn provide(&'a self, demand: &mut Demand<'a>)

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

Provides type based access to context intended for error reports. Read more

source

impl Error for Error

source

fn custom<T: Display>(msg: T) -> Error

Raised when there is general error when deserializing a type. Read more

source

fn invalid_type(unexp: Unexpected<'_>, exp: &dyn Expected) -> Self

Raised when a Deserialize receives a type different from what it was expecting. Read more

source

fn invalid_value(unexp: Unexpected<'_>, exp: &dyn Expected) -> Self

Raised when a Deserialize receives a value of the right type but that is wrong for some other reason. Read more

source

fn invalid_length(len: usize, exp: &dyn Expected) -> Self

Raised when deserializing a sequence or map and the input data contains too many or too few elements. Read more

source

fn unknown_variant(variant: &str, expected: &'static [&'static str]) -> Self

Raised when a Deserialize enum type received a variant with an unrecognized name. Read more

source

fn unknown_field(field: &str, expected: &'static [&'static str]) -> Self

Raised when a Deserialize struct type received a field with an unrecognized name. Read more

source

fn missing_field(field: &'static str) -> Self

Raised when a Deserialize struct type expected to receive a required field with a particular name but that field was not present in the input. Read more

source

fn duplicate_field(field: &'static str) -> Self

Raised when a Deserialize struct type received more than one of the same field. Read more

source

impl Error for Error

source

fn custom<T: Display>(msg: T) -> Error

Used when a Serialize implementation encounters any error while serializing a type. Read more

source

impl From<Error> for Error

source

fn from(j: Error) -> Self

Convert a serde_json::Error into an io::Error.

JSON syntax and data errors are turned into InvalidData IO errors. EOF errors are turned into UnexpectedEof IO errors.

use std::io;

enum MyError {
    Io(io::Error),
    Json(serde_json::Error),
}

impl From<serde_json::Error> for MyError {
    fn from(err: serde_json::Error) -> MyError {
        use serde_json::error::Category;
        match err.classify() {
            Category::Io => {
                MyError::Io(err.into())
            }
            Category::Syntax | Category::Data | Category::Eof => {
                MyError::Json(err)
            }
        }
    }
}

source