Struct Sig 

pub struct Sig {
    pub name: String,
    pub kind: SymbolKind,
    pub params: Vec<ParamInfo>,
    pub value_type: Option<InferredType>,
    pub value_ty: Option<Ty>,
    pub is_local: bool,
    pub param_annotations: Vec<Option<Ty>>,
    pub return_annotation: Option<Ty>,
}

Per-declaration signature summary (phase-0 stub).

Everything here is declaration-derived: a body edit that doesn’t touch the declaration line(s) must not change a Sig.

Fields

name: String

Canonical/qualified name, as indexed (e.g. knot.stitch).

kind: SymbolKind

Declaration kind.

params: Vec<ParamInfo>

Declared parameters (knots, stitches, externals).

value_type: Option<InferredType>

Type inferred from the initializer literal (VAR/CONST only), if the initializer is one. TM-2 (docs/typed-mode-spec.md §3): when the VAR/CONST also carries a : type annotation and that annotation resolves to a representable InferredType, the annotation replaces this value — annotation wins over inference (the firewall rule) — so every existing consumer of value_type (notably infer::collect_globals) picks up the annotated type automatically, with no seam change.

local_signature’s Param/Temp locals populate this field too (issue #530) — there it is never initializer-inferred (a local has no initializer-literal path here), only the downcast of the local’s own TM-2 : type annotation, None when unannotated or unresolved.

value_ty: Option<Ty>

A VAR/CONST’s declaration-derived type at full Ty fidelity (issue #1540) — None for every other signature-produced symbol kind, and for a VAR/CONST whose declaration determines no type at all. local_signature (issue #530) is the one other producer that populates this field: for a Param/Temp, it is the local’s own TM-2 : type annotation resolved the same way, None when the local is unannotated — this is precisely the field brink-ide::hover::inferred_local_type_str reads via db.local_signature.

This is the field every typed consumer reads (collect_globals in both this crate and brink-db’s narrowed mirror); value_type above stays exactly as narrow as it was, because it is the wire-adjacent domain infer_value_meta/hover share and widening it would leak Array/Map/Struct/Fn/Option/Range into that schema.

Populated in TM-2 firewall order — annotation first, then the initializer:

• an explicit : type annotation on the VAR/CONST, resolved by crate::annotations::resolve with no downcast (so Array<int>, Map<string, int>, a declared STRUCT name, fn(T…): R, Handle<K> and (since issue #1552) Option<T>/ Weighted<T> all survive — this is the ty_to_inferred_type gap issue #1540 closes. range still has no annotation grammar at all (crate::annotations::resolve has no arm for it — deferred pending demonstrated demand, docs/decision-log.md 2026-07-27), so a Ty::Range value can never actually reach this field yet;
• else the initializer literal, at the same fidelity ([literal_ty]): #[…] → Ty::Array, #{…} → Ty::Map, Name#{…} → Ty::Struct, plus every scalar/List<L> form infer_literal_type already covered;
• else a fn-value initializer ([declared_fn_type]) — a bare #fn(target, args…) literal (T1c follow-up, issue #712, docs/t1c-spec.md §4), or, on the native surface only, a bare name resolving to a function definition (docs/t1c-spec.md §2a, issue #1895; zero bound args, since the binding form has no native spelling). Either way the type is the bound prefix consumed from target’s own declaration-derived signature (param_annotations/return_annotation — a second, single-level signature() call, never the target’s body). An unannotated target param/return reads as Ty::Unknown in the row, the same conservative fallback declaration-derived typing always uses.

is_local: bool

Marked flow-private via a #@local directive (knots, stitches, VARs).

param_annotations: Vec<Option<Ty>>

TM-2 (docs/typed-mode-spec.md §3): declared param type annotations, positional (parallel to params) — None per-slot for an unannotated param, or one whose annotation doesn’t resolve to a Ty (void, fn(...), an unrecognized name — crate::check_annotations reports those separately). Knots/stitches only; empty for other symbol kinds.

return_annotation: Option<Ty>

TM-2: the function-header/stitch-header return type annotation (): type === on a knot, : type on a stitch — #1509 widened the grammar to stitches), resolved. None when absent, void, or unresolved. Knots and stitches only.

Trait Implementations

impl Clone for Sig

fn clone(&self) -> Sig

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Sig

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

Formats the value using the given formatter.

impl Eq for Sig

impl PartialEq for Sig

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for Sig