Trait MapKey 

pub trait MapKey<'input>: Sized {
    // Required method
    fn from_key(
        key: Cow<'input, str>,
        lex: &Lexer<'input>,
    ) -> Result<Self, Error>;
}

Internal adapter from a decoded JSON key to the user’s key type.

Sealed by the limited set of impls we provide; users who need a custom key type should hand-write the FromJson impl for the map or wrap the key in a newtype.

Returns Result because not every adapter is total — &'input str keys can only borrow, so escaped keys reject with InvalidEscape.

Required Methods

fn from_key(key: Cow<'input, str>, lex: &Lexer<'input>) -> Result<Self, Error>

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementations on Foreign Types

impl<'input> MapKey<'input> for &'input str

fn from_key(key: Cow<'input, str>, lex: &Lexer<'input>) -> Result<Self, Error>

Borrowing &'input str keys cannot represent escape-bearing keys, since the decoded form lives in a fresh allocation outside the input. Reject those at runtime; callers that expect escapes should use Cow<'input, str> or String.

impl<'input> MapKey<'input> for Cow<'input, str>

fn from_key(key: Self, _lex: &Lexer<'input>) -> Result<Self, Error>

impl<'input> MapKey<'input> for String

fn from_key(key: Cow<'input, str>, _lex: &Lexer<'input>) -> Result<Self, Error>

Implementors