Struct OpChain 

pub struct OpChain {
    pub head: AppExpr,
    pub tail: Vec<OpRhs>,
    pub before: Option<BeforeTail>,
}

A flattened binary-operator chain: head (op rhs)*, left-folded (with correct per-operator precedence/associativity) during elaboration. before is nxbfr’s postfix (e1 before e2), attached here rather than modeled at its own precedence level: nxbfr sits between nxif and nxlambda, i.e. above nxlor/OpChain’s own level, so parser.mly’s left operand is actually nxlambda (which also covers Fun/Overwrite) — attaching to OpChain alone misses (fun x -> e1) before e2/(x <- e1) before e2 as the left operand; such input is rejected here (a documented simplification, not a silent misparse). body is threaded through ExprErased (not boxed directly) to keep Expr a singleton SCC: a direct Box<Expr> field on OpChain would make OpChain itself part of Expr’s SCC (a second, non-Expr-variant self-loop edge), which is exactly the multi-type-cycle shape the module doc warns about.

Fields

head: AppExpr

tail: Vec<OpRhs>

before: Option<BeforeTail>

Trait Implementations

impl Clone for OpChain

fn clone(&self) -> OpChain

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for OpChain

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

Formats the value using the given formatter.

impl<__SyanMacro_Atom> Parse<__SyanMacro_Atom> for OpChain

where __SyanMacro_Atom: Spanned + Clone, AppExpr: Parse<__SyanMacro_Atom>, Vec<OpRhs>: Parse<__SyanMacro_Atom>, Option<BeforeTail>: Parse<__SyanMacro_Atom>,

type Error = ParseError<<__SyanMacro_Atom as Spanned>::Span>

Every error must be convertible to the universal one, so a field’s failure can become the enclosing type’s failure with no per-field where-predicate. Stating it HERE rather than at each derived impl is what keeps it out of the obligation graph: a per-field <FieldTy as Parse<Atom>>::Error: Into<…> predicate re-creates a projection cycle on a recursive field (E0275), which decycle’s bound-peeling does not break.

fn parse_stream<__SyanMacro_S: ParseStream<Atom = __SyanMacro_Atom>>( __syan_stream: &mut __SyanMacro_S, ) -> Result<Self, Self::Error>

Parse from a reborrowable stream.

fn parse(stream: impl IntoParseStream<Atom = Atom>) -> Result<Self, Self::Error>

Parse from anything that can become a stream — String, TokenStream, an existing stream.

fn attempt(self) -> Attempt<Self>

Wrap this value in Attempt, the atomic-parse marker: parsing an Attempt<Self> parses Self but rewinds the stream on failure (it requires Atom: Clone). This is the value constructor; value.attempt() is sugar for Attempt(value).

impl PartialEq for OpChain

fn eq(&self, other: &OpChain) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for OpChain

impl<__SyanMacro_Atom> Unparse<__SyanMacro_Atom> for OpChain

where AppExpr: Unparse<__SyanMacro_Atom>, Vec<OpRhs>: Unparse<__SyanMacro_Atom>, Option<BeforeTail>: Unparse<__SyanMacro_Atom>,

fn unparse<__Syan_Emitter: Emitter<__SyanMacro_Atom>>( &self, __syan_sink: &mut __Syan_Emitter, ) -> Result<(), <__Syan_Emitter as Emitter<__SyanMacro_Atom>>::Error>