Crate embassy_supervisor_syntax

Expand description

Parser and AST for the embassy-supervisor task-graph DSL.

This crate exists because a proc-macro crate type cannot export anything other than macros, so the grammar shared between embassy-supervisor-macros and tooling lives here instead. The AST is an internal contract: it is not a stable API and changes whenever the graph syntax does.

The parser checks grammatical shape (empty clauses, repeated paths, numeric ranges, and so on). Semantic checks such as duplicate names, missing fragments, or feature-gated constructs are left to callers.

Modules§

kw: Custom keywords used by the supervisor graph DSL.

Structs§

Access: One dataflow access discovered by scanning a #[dataflow] fn body.
AdoptedFn: A function adopted via a dataflow: [ ... ] clause.
CommonClauses: Clauses shared between node and pool declarations.
Dep: A single entry in a deps: [ ... ] list.
ExecutorItem: A parsed executor NAME; declaration.
Gated: A clause value together with the #[cfg(...)] attributes gating it.
GraphSpec: The parsed contents of a supervisor_graph! or supervisor_fragment! body.
NodeItem: A parsed node NAME = Mode, ...; declaration.
PoolItem: A parsed pool NAME = [Mode, ...], ...; declaration.
ProvideDecl: A single provides: entry: a resource-slot name, optionally #[cfg]-gated.
ResourceDecl: A single entry in a resources: [ ... ] list.
SignalDecl: A single entry in a reads: or writes: signal list.
VerbCall: A single dataflow verb call discovered in a #[dataflow] fn body.
VerbTable: Registry of read/write verbs used when scanning a #[dataflow] fn.

Enums§

Item: A top-level item inside a graph declaration.
ResourceKind: How a resources: entry hands its value to the task, as one value the consumers branch on instead of probing the marker fields.
StateInit: How a node’s state: initial value is specified.
TaskSource: How a node or pool member obtains its task future.

Constants§

BUILTIN_READS: Built-in read verb names recognised by the dataflow scanner.
BUILTIN_WRITES: Built-in write verb names recognised by the dataflow scanner.

Functions§

apply_default_executor: Apply the graph’s default executor to nodes and pools that do not write their own executor: clause. Only items whose task source is a task: fn or a spawn: path/partial call are eligible; parked nodes and verbatim spawn: closures keep the supervisor’s executor.
cfg_text: The #[cfg] attributes’ token text, normalized for predicate comparison.
check_signal_list: Check that a reads: or writes: list is non-empty and has no duplicates.
dataflow_attr: Unwrap a #[dataflow] attribute, including any #[cfg_attr(...)] wrapper.
is_dataflow_attr: Return true if attr is a #[dataflow] attribute, written directly or wrapped in #[cfg_attr(.., dataflow)]. See dataflow_attr.
item_executor: Return the executor: an item routes through, if it names one.
item_ident_cfg: Return the identifying name and #[cfg] attributes of an item, if it has one.
item_resources: Return the resource declarations for an item, if any.
item_signal_entries: Iterate over every signal entry declared by an item.
name_string: Convert an identifier to a lower-case, hyphenated string.
node_param: Find the name of the function argument whose type contains TaskNode.
normalize_fragment_crate: Rewrite bare crate paths in a fragment body into $crate.
parse_dep_list: Parse a bracketed dependency list of the form [A, B ready, C ready bound].
parse_mode_list: Parse a bracketed list of pool member mode identifiers.
parse_node: Parse a node NAME = Mode, ...; declaration after the leading node keyword.
parse_pool: Parse a pool NAME = [Mode, ...], ...; declaration after the leading pool keyword.
parse_resource_list: Parse a bracketed resource list such as [SLOT: Type local shared].
parse_signal_list: Parse a bracketed signal list such as [S, T observed, U beat].
path_to_string: Render a syn::Path as its ::-separated string form.
peek_kind_marker: Look ahead for a resource kind marker (local, consume, shared, divisible, or serialized).
rewrite_verb_calls: Walk a #[dataflow] fn body and rewrite recognised verb calls.
scan_dataflow: Scan Rust source for #[dataflow] functions and append their accesses to out.
substitute_dollar_crate: Replace every $crate occurrence in stream with replacement.
task_source: Resolve the optional spawn: / task: clauses into a TaskSource.
verb_table_of: Build a VerbTable from a #[dataflow(...)] attribute.