dfir_lang/graph/ops/
mod.rs

1//! DFIR's operators
2
3use std::collections::HashMap;
4use std::fmt::{Debug, Display};
5use std::ops::{Bound, RangeBounds};
6use std::sync::OnceLock;
7
8use documented::DocumentedVariants;
9use proc_macro2::{Ident, Literal, Span, TokenStream};
10use quote::quote_spanned;
11use serde::{Deserialize, Serialize};
12use slotmap::Key;
13use syn::punctuated::Punctuated;
14use syn::{Expr, Token, parse_quote_spanned};
15
16use super::{
17    GraphLoopId, GraphNode, GraphNodeId, GraphSubgraphId, OpInstGenerics, OperatorInstance,
18    PortIndexValue,
19};
20use crate::diagnostic::{Diagnostic, Diagnostics, Level};
21use crate::parse::{Operator, PortIndex};
22
23/// The delay (soft barrier) type, for each input to an operator if needed.
24#[derive(Clone, Copy, PartialOrd, Ord, PartialEq, Eq, Debug, Serialize, Deserialize)]
25pub enum DelayType {
26    /// Input must be collected over the previous tick.
27    Tick,
28    /// Input must be collected over the previous tick but also not cause a new tick to occur.
29    TickLazy,
30    /// Input must be collected over the previous loop iteration. Causes the loop to re-fire.
31    Loop,
32    /// Input must be collected over the previous loop iteration. Does NOT cause the loop to re-fire.
33    LoopLazy,
34}
35
36/// Specification of the named (or unnamed) ports for an operator's inputs or outputs.
37pub enum PortListSpec {
38    /// Any number of unnamed (or optionally named) ports.
39    Variadic,
40    /// A specific number of named ports.
41    Fixed(Punctuated<PortIndex, Token![,]>),
42}
43
44/// An instance of this struct represents a single dfir operator.
45pub struct OperatorConstraints {
46    /// Operator's name.
47    pub name: &'static str,
48    /// Operator categories, for docs.
49    pub categories: &'static [OperatorCategory],
50
51    // TODO: generic argument ranges.
52    /// Input argument range required to not show an error.
53    pub hard_range_inn: &'static dyn RangeTrait<usize>,
54    /// Input argument range required to not show a warning.
55    pub soft_range_inn: &'static dyn RangeTrait<usize>,
56    /// Output argument range required to not show an error.
57    pub hard_range_out: &'static dyn RangeTrait<usize>,
58    /// Output argument range required to not show an warning.
59    pub soft_range_out: &'static dyn RangeTrait<usize>,
60    /// Number of arguments i.e. `operator(a, b, c)` has `num_args = 3`.
61    pub num_args: usize,
62    /// How many persistence lifetime arguments can be provided.
63    pub persistence_args: &'static dyn RangeTrait<usize>,
64    // /// How many (non-persistence) lifetime arguments can be provided.
65    // pub lifetime_args: &'static dyn RangeTrait<usize>,
66    /// How many generic type arguments can be provided.
67    pub type_args: &'static dyn RangeTrait<usize>,
68    /// If this operator receives external inputs and therefore must be in
69    /// stratum 0.
70    pub is_external_input: bool,
71    /// Flo semantics type.
72    pub flo_type: Option<FloType>,
73
74    /// What named or numbered input ports to expect?
75    pub ports_inn: Option<fn() -> PortListSpec>,
76    /// What named or numbered output ports to expect?
77    pub ports_out: Option<fn() -> PortListSpec>,
78
79    /// Determines if this input must be preceeded by a stratum barrier.
80    pub input_delaytype_fn: fn(&PortIndexValue) -> Option<DelayType>,
81    /// The operator's codegen. Returns code that is emited is several different locations. See [`OperatorWriteOutput`].
82    pub write_fn: WriteFn,
83}
84
85/// Type alias for [`OperatorConstraints::write_fn`]'s type.
86pub type WriteFn = fn(&WriteContextArgs<'_>, &mut Diagnostics) -> Result<OperatorWriteOutput, ()>;
87
88impl Debug for OperatorConstraints {
89    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
90        f.debug_struct("OperatorConstraints")
91            .field("name", &self.name)
92            .field("hard_range_inn", &self.hard_range_inn)
93            .field("soft_range_inn", &self.soft_range_inn)
94            .field("hard_range_out", &self.hard_range_out)
95            .field("soft_range_out", &self.soft_range_out)
96            .field("num_args", &self.num_args)
97            .field("persistence_args", &self.persistence_args)
98            .field("type_args", &self.type_args)
99            .field("is_external_input", &self.is_external_input)
100            .field("ports_inn", &self.ports_inn)
101            .field("ports_out", &self.ports_out)
102            // .field("input_delaytype_fn", &self.input_delaytype_fn)
103            // .field("flow_prop_fn", &self.flow_prop_fn)
104            // .field("write_fn", &self.write_fn)
105            .finish()
106    }
107}
108
109/// The code generated and returned by a [`OperatorConstraints::write_fn`].
110/// **Important**: When destructuring this struct in delegating operators, list all fields
111/// explicitly rather than using `..` to ensure new fields are not silently dropped.
112#[derive(Default)]
113pub struct OperatorWriteOutput {
114    /// Code which runs once outside any subgraphs to set up external state
115    /// (channels, network connections, etc.) to be used by the subgraph.
116    pub write_prologue: TokenStream,
117    /// Iterator (or pusherator) code inside the subgraphs. The code for each
118    /// operator is emitted in order.
119    ///
120    /// Emitted code should assign to [`WriteContextArgs::ident`] and use
121    /// [`WriteContextArgs::inputs`] (pull `Stream`s) or
122    /// [`WriteContextArgs::outputs`] (push `Sink`s).
123    pub write_iterator: TokenStream,
124    /// Code which runs after `Stream`s/`Sink`s have been run. Mainly for flushing IO.
125    pub write_iterator_after: TokenStream,
126    /// Code which runs at the end of each tick, after all subgraphs have run.
127    /// Used for resetting state with `'tick` persistence.
128    pub write_tick_end: TokenStream,
129}
130
131/// Convenience range: zero or more (any number).
132pub const RANGE_ANY: &'static dyn RangeTrait<usize> = &(0..);
133/// Convenience range: exactly zero.
134pub const RANGE_0: &'static dyn RangeTrait<usize> = &(0..=0);
135/// Convenience range: exactly one.
136pub const RANGE_1: &'static dyn RangeTrait<usize> = &(1..=1);
137
138/// Helper to write the `write_iterator` portion of [`OperatorConstraints::write_fn`] output for
139/// unary identity operators.
140pub fn identity_write_iterator_fn(
141    &WriteContextArgs {
142        root,
143        op_span,
144        ident,
145        inputs,
146        outputs,
147        is_pull,
148        op_inst:
149            OperatorInstance {
150                generics: OpInstGenerics { type_args, .. },
151                ..
152            },
153        ..
154    }: &WriteContextArgs<'_>,
155) -> TokenStream {
156    let generic_type = type_args
157        .first()
158        .map(quote::ToTokens::to_token_stream)
159        .unwrap_or_else(|| quote_spanned!(op_span=> _));
160
161    if is_pull {
162        let input = &inputs[0];
163        quote_spanned! {op_span=>
164            let #ident = {
165                fn check_input<Pull, Item>(pull: Pull) -> impl #root::dfir_pipes::pull::Pull<Item = Item, Meta = Pull::Meta, CanPend = Pull::CanPend, CanEnd = Pull::CanEnd>
166                where
167                    Pull: #root::dfir_pipes::pull::Pull<Item = Item>,
168                {
169                    pull
170                }
171                check_input::<_, #generic_type>(#input)
172            };
173        }
174    } else {
175        let output = &outputs[0];
176        quote_spanned! {op_span=>
177            let #ident = {
178                fn check_output<Psh, Item>(push: Psh) -> impl #root::dfir_pipes::push::Push<Item, (), CanPend = Psh::CanPend>
179                where
180                    Psh: #root::dfir_pipes::push::Push<Item, ()>,
181                {
182                    push
183                }
184                check_output::<_, #generic_type>(#output)
185            };
186        }
187    }
188}
189
190/// [`OperatorConstraints::write_fn`] for unary identity operators.
191pub const IDENTITY_WRITE_FN: WriteFn = |write_context_args, _| {
192    let write_iterator = identity_write_iterator_fn(write_context_args);
193    Ok(OperatorWriteOutput {
194        write_iterator,
195        ..Default::default()
196    })
197};
198
199/// Helper to write the `write_iterator` portion of [`OperatorConstraints::write_fn`] output for
200/// the null operator - an operator that ignores all inputs and produces no output.
201pub fn null_write_iterator_fn(
202    &WriteContextArgs {
203        root,
204        op_span,
205        ident,
206        inputs,
207        outputs,
208        is_pull,
209        op_inst:
210            OperatorInstance {
211                generics: OpInstGenerics { type_args, .. },
212                ..
213            },
214        ..
215    }: &WriteContextArgs<'_>,
216) -> TokenStream {
217    let default_type = parse_quote_spanned! {op_span=> _};
218    let iter_type = type_args.first().unwrap_or(&default_type);
219
220    if is_pull {
221        quote_spanned! {op_span=>
222            let #ident = #root::dfir_pipes::pull::poll_fn({
223                #(
224                    let mut #inputs = ::std::boxed::Box::pin(#inputs);
225                )*
226                move |_cx| {
227                    // Make sure to poll all `#inputs` to completion.
228                    // NOTE(mingwei): `null()` can only have 0 or 1 inputs, though.
229                    // TODO(mingwei): Do we actually need to poll to completion or can we short-circuit?
230                    #(
231                        let #inputs = #root::dfir_pipes::pull::Pull::pull(
232                            ::std::pin::Pin::as_mut(&mut #inputs),
233                            <_ as #root::dfir_pipes::Context>::from_task(_cx),
234                        );
235                    )*
236                    #(
237                        if let #root::dfir_pipes::pull::PullStep::Pending(_) = #inputs {
238                            return #root::dfir_pipes::pull::PullStep::Pending(#root::dfir_pipes::Yes);
239                        }
240                    )*
241                    #root::dfir_pipes::pull::PullStep::<_, _, #root::dfir_pipes::Yes, _>::Ended(#root::dfir_pipes::Yes)
242                }
243            });
244        }
245    } else {
246        quote_spanned! {op_span=>
247            #[allow(clippy::let_unit_value)]
248            let _ = (#(#outputs),*);
249            let #ident = #root::dfir_pipes::push::for_each::<_, #iter_type>(::std::mem::drop::<#iter_type>);
250        }
251    }
252}
253
254/// [`OperatorConstraints::write_fn`] for the null operator - an operator that ignores all inputs
255/// and produces no output.
256pub const NULL_WRITE_FN: WriteFn = |write_context_args, _| {
257    let write_iterator = null_write_iterator_fn(write_context_args);
258    Ok(OperatorWriteOutput {
259        write_iterator,
260        ..Default::default()
261    })
262};
263
264macro_rules! declare_ops {
265    ( $( $mod:ident :: $op:ident, )* ) => {
266        $( pub(crate) mod $mod; )*
267        /// All DFIR operators.
268        pub const OPERATORS: &[OperatorConstraints] = &[
269            $( $mod :: $op, )*
270        ];
271    };
272}
273declare_ops![
274    all_iterations::ALL_ITERATIONS,
275    anti_join::ANTI_JOIN,
276    assert::ASSERT,
277    assert_eq::ASSERT_EQ,
278    batch::BATCH,
279    batch_eager::BATCH_EAGER,
280    batch_lazy::BATCH_LAZY,
281    chain::CHAIN,
282    chain_first_n::CHAIN_FIRST_N,
283    _counter::_COUNTER,
284    cross_join::CROSS_JOIN,
285    cross_join_multiset::CROSS_JOIN_MULTISET,
286    cross_singleton::CROSS_SINGLETON,
287    demux_enum::DEMUX_ENUM,
288    dest_file::DEST_FILE,
289    dest_sink::DEST_SINK,
290    dest_sink_serde::DEST_SINK_SERDE,
291    difference::DIFFERENCE,
292    enumerate::ENUMERATE,
293    filter::FILTER,
294    filter_map::FILTER_MAP,
295    flat_map::FLAT_MAP,
296    flat_map_stream_blocking::FLAT_MAP_STREAM_BLOCKING,
297    flatten::FLATTEN,
298    flatten_stream_blocking::FLATTEN_STREAM_BLOCKING,
299    fold::FOLD,
300    fold_no_replay::FOLD_NO_REPLAY,
301    for_each::FOR_EACH,
302    identity::IDENTITY,
303    initialize::INITIALIZE,
304    inspect::INSPECT,
305    iter_ref::ITER_REF,
306    join::JOIN,
307    join_fused::JOIN_FUSED,
308    join_fused_lhs::JOIN_FUSED_LHS,
309    join_fused_rhs::JOIN_FUSED_RHS,
310    join_multiset::JOIN_MULTISET,
311    join_multiset_half::JOIN_MULTISET_HALF,
312    fold_keyed::FOLD_KEYED,
313    reduce_keyed::REDUCE_KEYED,
314    lattice_bimorphism::LATTICE_BIMORPHISM,
315    _lattice_fold_batch::_LATTICE_FOLD_BATCH,
316    lattice_fold::LATTICE_FOLD,
317    _lattice_join_fused_join::_LATTICE_JOIN_FUSED_JOIN,
318    lattice_reduce::LATTICE_REDUCE,
319    map::MAP,
320    union::UNION,
321    multiset_delta::MULTISET_DELTA,
322    defer_signal::DEFER_SIGNAL,
323    defer_tick::DEFER_TICK,
324    defer_tick_lazy::DEFER_TICK_LAZY,
325    null::NULL,
326    partition::PARTITION,
327    persist::PERSIST,
328    resolve_futures::RESOLVE_FUTURES,
329    resolve_futures_blocking::RESOLVE_FUTURES_BLOCKING,
330    resolve_futures_blocking_ordered::RESOLVE_FUTURES_BLOCKING_ORDERED,
331    resolve_futures_ordered::RESOLVE_FUTURES_ORDERED,
332    reduce::REDUCE,
333    reduce_no_replay::REDUCE_NO_REPLAY,
334    scan::SCAN,
335    scan_async_blocking::SCAN_ASYNC_BLOCKING,
336    spin::SPIN,
337    sort::SORT,
338    sort_by_key::SORT_BY_KEY,
339    source_file::SOURCE_FILE,
340    source_interval::SOURCE_INTERVAL,
341    source_iter::SOURCE_ITER,
342    source_json::SOURCE_JSON,
343    source_stdin::SOURCE_STDIN,
344    source_stream::SOURCE_STREAM,
345    source_stream_serde::SOURCE_STREAM_SERDE,
346    state::STATE,
347    state_by::STATE_BY,
348    tee::TEE,
349    unique::UNIQUE,
350    unzip::UNZIP,
351    zip::ZIP,
352    zip_longest::ZIP_LONGEST,
353];
354
355/// Get the operator lookup table, generating it if needed.
356pub fn operator_lookup() -> &'static HashMap<&'static str, &'static OperatorConstraints> {
357    pub static OPERATOR_LOOKUP: OnceLock<HashMap<&'static str, &'static OperatorConstraints>> =
358        OnceLock::new();
359    OPERATOR_LOOKUP.get_or_init(|| OPERATORS.iter().map(|op| (op.name, op)).collect())
360}
361/// Find an operator by [`GraphNode`].
362pub fn find_node_op_constraints(node: &GraphNode) -> Option<&'static OperatorConstraints> {
363    if let GraphNode::Operator(operator) = node {
364        find_op_op_constraints(operator)
365    } else {
366        None
367    }
368}
369/// Find an operator by an AST [`Operator`].
370pub fn find_op_op_constraints(operator: &Operator) -> Option<&'static OperatorConstraints> {
371    let name = &*operator.name_string();
372    operator_lookup().get(name).copied()
373}
374
375/// Context arguments provided to [`OperatorConstraints::write_fn`].
376#[derive(Clone)]
377pub struct WriteContextArgs<'a> {
378    /// `dfir` crate name for `use #root::something`.
379    pub root: &'a TokenStream,
380    /// `context` ident, the name of the provided
381    /// [`dfir_rs::scheduled::Context`](https://hydro.run/rustdoc/dfir_rs/scheduled/context/struct.Context.html).
382    pub context: &'a Ident,
383    /// `df` ident, the name of the
384    /// [`dfir_rs::scheduled::graph::Dfir`](https://hydro.run/rustdoc/dfir_rs/scheduled/graph/struct.Dfir.html)
385    /// instance.
386    pub df_ident: &'a Ident,
387    /// Subgraph ID in which this operator is contained.
388    pub subgraph_id: GraphSubgraphId,
389    /// Node ID identifying this operator in the flat or partitioned graph meta-datastructure.
390    pub node_id: GraphNodeId,
391    /// Loop ID in which this operator is contained, or `None` if not in a loop.
392    pub loop_id: Option<GraphLoopId>,
393    /// The source span of this operator.
394    pub op_span: Span,
395    /// Tag for this operator appended to the generated identifier.
396    pub op_tag: Option<String>,
397    /// Identifier for a function to call when doing work outside the stream.
398    pub work_fn: &'a Ident,
399    /// Identifier for a function to wrap futures when doing work outside the stream.
400    pub work_fn_async: &'a Ident,
401
402    /// Ident the `Stream` or `Sink` should be assigned to.
403    pub ident: &'a Ident,
404    /// If a pull `Stream` (true) or push `Sink` (false) should be used.
405    pub is_pull: bool,
406    /// Input `Stream` operator idents (or ref idents; used for pull).
407    pub inputs: &'a [Ident],
408    /// Output `Sink` operator idents (or ref idents; used for push).
409    pub outputs: &'a [Ident],
410
411    /// Operator name.
412    pub op_name: &'static str,
413    /// Operator instance arguments object.
414    pub op_inst: &'a OperatorInstance,
415    /// Arguments provided by the user into the operator as arguments.
416    /// I.e. the `a, b, c` in `-> my_op(a, b, c) -> `.
417    ///
418    /// These arguments include singleton postprocessing codegen, with
419    /// [`std::cell::RefCell::borrow_mut`] code pre-generated.
420    pub arguments: &'a Punctuated<Expr, Token![,]>,
421}
422impl WriteContextArgs<'_> {
423    /// Generate a (almost certainly) unique identifier with the given suffix.
424    ///
425    /// Includes the subgraph and node IDs in the generated identifier.
426    ///
427    /// This will always return the same identifier for a given `suffix`.
428    pub fn make_ident(&self, suffix: impl AsRef<str>) -> Ident {
429        Ident::new(
430            &format!(
431                "sg_{:?}_node_{:?}_{}",
432                self.subgraph_id.data(),
433                self.node_id.data(),
434                suffix.as_ref(),
435            ),
436            self.op_span,
437        )
438    }
439
440    /// Returns the given number of persistence arguments, defaulting to `'tick` when unspecified.
441    pub fn persistence_args<const N: usize>(
442        &self,
443        diagnostics: &mut Diagnostics,
444    ) -> [Persistence; N] {
445        let len = self.op_inst.generics.persistence_args.len();
446        if 0 != len && 1 != len && N != len {
447            diagnostics.push(Diagnostic::spanned(
448                self.op_span,
449                Level::Error,
450                format!(
451                    "The operator `{}` only accepts 0, 1, or {} persistence arguments",
452                    self.op_name, N
453                ),
454            ));
455        }
456
457        let mut out = [Persistence::Tick; N];
458        self.op_inst
459            .generics
460            .persistence_args
461            .iter()
462            .copied()
463            .cycle() // Re-use the first element for both persistences.
464            .take(N)
465            .enumerate()
466            .for_each(|(i, p)| {
467                out[i] = p;
468            });
469        out
470    }
471}
472
473/// An object-safe version of [`RangeBounds`].
474pub trait RangeTrait<T>: Send + Sync + Debug
475where
476    T: ?Sized,
477{
478    /// Start (lower) bound.
479    fn start_bound(&self) -> Bound<&T>;
480    /// End (upper) bound.
481    fn end_bound(&self) -> Bound<&T>;
482    /// Returns if `item` is contained in this range.
483    fn contains(&self, item: &T) -> bool
484    where
485        T: PartialOrd<T>;
486
487    /// Turn this range into a human-readable string.
488    fn human_string(&self) -> String
489    where
490        T: Display + PartialEq,
491    {
492        match (self.start_bound(), self.end_bound()) {
493            (Bound::Unbounded, Bound::Unbounded) => "any number of".to_owned(),
494
495            (Bound::Included(n), Bound::Included(x)) if n == x => {
496                format!("exactly {}", n)
497            }
498            (Bound::Included(n), Bound::Included(x)) => {
499                format!("at least {} and at most {}", n, x)
500            }
501            (Bound::Included(n), Bound::Excluded(x)) => {
502                format!("at least {} and less than {}", n, x)
503            }
504            (Bound::Included(n), Bound::Unbounded) => format!("at least {}", n),
505            (Bound::Excluded(n), Bound::Included(x)) => {
506                format!("more than {} and at most {}", n, x)
507            }
508            (Bound::Excluded(n), Bound::Excluded(x)) => {
509                format!("more than {} and less than {}", n, x)
510            }
511            (Bound::Excluded(n), Bound::Unbounded) => format!("more than {}", n),
512            (Bound::Unbounded, Bound::Included(x)) => format!("at most {}", x),
513            (Bound::Unbounded, Bound::Excluded(x)) => format!("less than {}", x),
514        }
515    }
516}
517
518impl<R, T> RangeTrait<T> for R
519where
520    R: RangeBounds<T> + Send + Sync + Debug,
521{
522    fn start_bound(&self) -> Bound<&T> {
523        self.start_bound()
524    }
525
526    fn end_bound(&self) -> Bound<&T> {
527        self.end_bound()
528    }
529
530    fn contains(&self, item: &T) -> bool
531    where
532        T: PartialOrd<T>,
533    {
534        self.contains(item)
535    }
536}
537
538/// Persistence lifetimes: `'none`, `'loop`, `'tick`, or `'static`.
539#[derive(Clone, Copy, PartialOrd, Ord, PartialEq, Eq, Debug, Serialize, Deserialize)]
540pub enum Persistence {
541    /// Persistence for one "tick" (or loop iteration), i.e. no persistance at all
542    Tick,
543    /// Persistence across the entire program execution.
544    Static,
545}
546impl Persistence {
547    /// Returns a lowercase string for the persistence type.
548    pub fn to_str_lowercase(self) -> &'static str {
549        match self {
550            Persistence::Tick => "tick",
551            Persistence::Static => "static",
552        }
553    }
554}
555
556/// Helper which creates a error message string literal for when the Tokio runtime is not found.
557fn make_missing_runtime_msg(op_name: &str) -> Literal {
558    Literal::string(&format!(
559        "`{}()` must be used within a Tokio runtime. For example, use `#[dfir_rs::main]` on your main method.",
560        op_name
561    ))
562}
563
564/// Operator categories, for docs.
565#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord, Hash, DocumentedVariants)]
566pub enum OperatorCategory {
567    /// Maps: Simple one-in-one-out operators.
568    Map,
569    /// Filters: One-in zero-or-one-out operators.
570    Filter,
571    /// Flattens: One-in multiple-out operators.
572    Flatten,
573    /// Folds: Operators which accumulate elements together.
574    Fold,
575    /// Keyed Folds: Operators which accumulate elements together by key.
576    KeyedFold,
577    /// Lattice Folds: Folds based on lattice-merge.
578    LatticeFold,
579    /// Persistent Operators: Persistent (stateful) operators.
580    Persistence,
581    /// Multi-Input Operators: Operators with multiple inputs.
582    MultiIn,
583    /// Multi-Output Operators: Operators with multiple outputs.
584    MultiOut,
585    /// Sources: Operators which produce output elements (and consume no inputs).
586    Source,
587    /// Sinks: Operators which consume input elements (and produce no outputs).
588    Sink,
589    /// Control Flow Operators: Operators which affect control flow/scheduling.
590    Control,
591    /// Compiler Fusion Operators: Operators which are necessary to implement certain optimizations and rewrite rules.
592    CompilerFusionOperator,
593    /// Windowing Operators: Operators for windowing `loop` inputs.
594    Windowing,
595    /// Un-Windowing Operators: Operators for collecting `loop` outputs.
596    Unwindowing,
597}
598impl OperatorCategory {
599    /// Human-readible heading name, for docs.
600    pub fn name(self) -> &'static str {
601        self.get_variant_docs().split_once(":").unwrap().0
602    }
603    /// Human description, for docs.
604    pub fn description(self) -> &'static str {
605        self.get_variant_docs().split_once(":").unwrap().1
606    }
607}
608
609/// Operator type for Flo semantics.
610#[derive(Clone, Copy, PartialOrd, Ord, PartialEq, Eq, Debug)]
611pub enum FloType {
612    /// A source operator, which must be at the top level.
613    Source,
614    /// A windowing operator, for moving data into a loop context.
615    Windowing,
616    /// A lazy windowing operator — moves data into a loop context but does not trigger the loop.
617    /// Data is dropped if the loop does not fire that tick.
618    WindowingLazy,
619    /// An eager windowing operator — moves data into a loop context and always triggers the loop,
620    /// even when the windowed input is empty. Only valid at the entry of a root-level loop (it is
621    /// disallowed in nested loops, where it would prevent the fixpoint iteration from terminating).
622    WindowingEager,
623    /// An un-windowing operator, for moving data out of a loop context.
624    Unwindowing,
625}
dfir_lang/graph/ops/mod.rs

dfir_lang/graph/ops/
mod.rs
