Struct toml_span::de_helpers::TableHelper

pub struct TableHelper<'de> {
    pub table: Table<'de>,
    pub errors: Vec<Error>,
    /* private fields */
}

A helper for dealing with ValueInner::Table

Fields

table: Table<'de>

The table the helper is operating upon

errors: Vec<Error>

The errors accumulated while deserializing

Implementations

impl<'de> TableHelper<'de>

pub fn new(value: &mut Value<'de>) -> Result<Self, DeserError>

Creates a helper for the value, failing if it is not a table

pub fn contains(&self, name: &'de str) -> bool

Returns true if the table contains the specified key

pub fn take(&mut self, name: &'static str) -> Option<(Key<'de>, Value<'de>)>

Takes the specified key and its value if it exists

pub fn required<T: Deserialize<'de>>( &mut self, name: &'static str, ) -> Result<T, Error>

Attempts to deserialize the specified key

Errors that occur when calling this method are automatically added to the set of errors that are reported from Self::finalize, so not early returning if this method fails will still report the error by default

Errors

• The key does not exist
• The Deserialize implementation for the type returns an error

pub fn required_s<T: Deserialize<'de>>( &mut self, name: &'static str, ) -> Result<Spanned<T>, Error>

The same as Self::required, except it returns a Spanned

pub fn optional<T: Deserialize<'de>>(&mut self, name: &'static str) -> Option<T>

Attempts to deserialize the specified key, if it exists

Note that if the key exists but deserialization fails, an error will be appended and if Self::finalize is called it will return that error along with any others that occurred

pub fn optional_s<T: Deserialize<'de>>( &mut self, name: &'static str, ) -> Option<Spanned<T>>

The same as Self::optional, except it returns a Spanned

pub fn finalize( self, original: Option<&mut Value<'de>>, ) -> Result<(), DeserError>

Called when you are finished with this TableHelper

If errors have been accumulated when using this TableHelper, this will return an error with all of those errors.

Additionally, if Option::None is passed, any keys that still exist in the table will be added to an ErrorKind::UnexpectedKeys error, which can be considered equivalent to #[serde(deny_unknown_fields)]

If you want simulate #[serde(flatten)] you can instead put that table back in its original value during this step

Trait Implementations

impl<'de> From<(BTreeMap<Key<'de>, Value<'de>>, Span)> for TableHelper<'de>

fn from((table, span): (Table<'de>, Span)) -> Self

Converts to this type from the input type.