Struct Checkpoint 

pub struct Checkpoint { /* private fields */ }

Saved lexer position + nesting depth, restorable via Lexer::restore.

Returned by Lexer::checkpoint. The two fields together capture everything a typed consumer might mutate while exploring an input speculatively — the byte cursor and the container-frame stack depth. Restoring rewinds both, putting the lexer back into the exact state it was in when the checkpoint was taken.

Used by enum dispatch for representations that must try a variant and retry another on failure (#[bourne(untagged)]) or that must locate a tag field before parsing the rest of the object (#[bourne(tag = "...")]).

Trait Implementations

impl Clone for Checkpoint

fn clone(&self) -> Checkpoint

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for Checkpoint

impl Debug for Checkpoint

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

Formats the value using the given formatter.