Struct BasicParser 

pub struct BasicParser {

    scanner: BasicScanner,
    events: Vec<Event>,
    event_index: usize,
    state: ParserState,
    state_stack: Vec<ParserState>,
    position: Position,
    pending_anchor: Option<String>,
    pending_anchor_line: Option<usize>,
    last_key_marker_line: Option<usize>,
    last_key_marker_column: Option<usize>,
    just_closed_inline_wrap: bool,
    inline_wrap_column: Option<usize>,
    pending_tag: Option<String>,
    pending_tag_line: Option<usize>,
    last_token_type: Option<TokenType>,
    scanning_error: Option<Error>,
    yaml_version: Option<(u8, u8)>,
    tag_directives: Vec<(String, String)>,
    tag_resolver: TagResolver,
    defined_anchors: HashSet<String>,
    last_value_token_line: Option<usize>,
    explicit_key_pending: bool,
    implicit_flow_pair_depth: usize,
}

Basic parser implementation that converts tokens to events

Fields

scanner: BasicScanner

events: Vec<Event>

event_index: usize

state: ParserState

state_stack: Vec<ParserState>

position: Position

pending_anchor: Option<String>

pending_anchor_line: Option<usize>

Line where pending_anchor was set. Used to distinguish a “freestanding” anchor (alone on its own line — belongs to the upcoming collection) from an “inline” anchor (same line as the next key — belongs to that key). yaml-test-suite 6BFJ, 9KAX.

last_key_marker_line: Option<usize>

Line of the most recent ? Key marker. Used to detect when an explicit-key construct has an inline single-pair mapping as its key (yaml-test-suite M2N8/00, M2N8/01, V9D5).

last_key_marker_column: Option<usize>

Column of the most recent ? Key marker. Used in V9D5: when a : arrives at the same column as the most recent ? on a later line, it’s the explicit value separator — close any inline-wrapped inner mapping first.

just_closed_inline_wrap: bool

Set when an explicit value separator just closed an inline- wrapped key. The next <scalar>:<scalar> on the same line should also be wrapped in an inner mapping (V9D5’s value side).

inline_wrap_column: Option<usize>

Column of an open inline-wrap mapping (V9D5). Used to detect the matching explicit-value separator and close it.

pending_tag: Option<String>

pending_tag_line: Option<usize>

Same idea as pending_anchor_line but for tags. Used to detect a freestanding tag in block-sequence context that should be flushed as the previous item’s empty value rather than carried onto the next item (yaml-test-suite FH7J).

last_token_type: Option<TokenType>

scanning_error: Option<Error>

yaml_version: Option<(u8, u8)>

tag_directives: Vec<(String, String)>

tag_resolver: TagResolver

defined_anchors: HashSet<String>

Anchor names that have been defined so far in the stream. Used to validate that aliases (*name) reference a known anchor (YAML 1.2 §6.9.2). Forward references are forbidden, and we never reset this set — once defined, an anchor remains referenceable for the rest of the parse, matching common loader semantics.

last_value_token_line: Option<usize>

Line of the most recent : Value token. Used by the BlockMappingValue heuristic to tell apart “same-line value scalar” (6M2F) from “next-line sibling key” (6KGN).

explicit_key_pending: bool

True while we’re holding an explicit ? key that has not yet received its :. Used at end-of-stream to distinguish a spec-legal ? key with implicit empty value from a missing-: bare scalar (yaml-test-suite 7MNF).

implicit_flow_pair_depth: usize

Counts implicit single-pair flow mappings still open. A , or ] while this is > 0 closes the innermost implicit mapping before continuing the outer flow sequence (§7.5).

Implementations

impl BasicParser

pub fn new(input: String) -> Self

Create a new streaming parser (lazy parsing)

pub fn with_limits(input: String, limits: Limits) -> Self

Create a new streaming parser with custom limits

pub fn new_eager(input: String) -> Self

Create a new parser with eager parsing (for compatibility)

pub fn new_eager_with_limits(input: String, limits: Limits) -> Self

Create a new parser with eager parsing and custom limits

pub fn from_scanner(scanner: BasicScanner) -> Self

Create parser from existing scanner

fn parse_all(&mut self) -> Result<()>

Parse all tokens into events

fn check_directive_context(&self, pos: Position, name: &str) -> Result<()>

YAML 1.2 §6.8: directives may appear only before the first document (StreamStart / ImplicitDocumentStart) or after an explicit ... (DocumentEnd). Anywhere else they’re invalid.

fn create_implicit_document_start(&mut self, position: Position) -> Event

Create implicit document start event with directives

fn validate_final_state(&self) -> Result<()>

Validate that the parser is in a valid final state

fn generate_next_event(&mut self) -> Result<()>

Generate the next event by processing the next token

fn process_token(&mut self, token: Token) -> Result<()>

Process a single token and generate appropriate events

fn handle_node_completion(&mut self)

Handle completion of a node (scalar or collection) and manage mapping state transitions

impl BasicParser

pub fn take_scanning_error(&mut self) -> Option<Error>

Check if there was a scanning error

Trait Implementations

impl Debug for BasicParser

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

Formats the value using the given formatter.

impl Default for BasicParser

fn default() -> Self

Returns the “default value” for a type.

impl Parser for BasicParser

fn check_event(&self) -> bool

Check if there are more events available

fn peek_event(&self) -> Result<Option<&Event>>

Peek at the next event without consuming it

fn get_event(&mut self) -> Result<Option<Event>>

Get the next event, consuming it

fn reset(&mut self)

Reset the parser state

fn position(&self) -> Position

Get the current position in the input