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#246 Adds TaskSeqDynamicInfo<'T> and TaskSeqDynamic<'T> types that implement the dynamic (ResumptionDynamicInfo-based) execution path for taskSeq computation expressions. This fixes the NotImplementedException raised when taskSeq is used in contexts where the F# compiler cannot emit static resumable code, such as F# Interactive (FSI) or top-level functions. Key changes: - TaskSeqDynamicInfo<'T>: concrete ResumptionDynamicInfo subclass that handles MoveNext transitions (same logic as the static MoveNextMethodImpl) - TaskSeqDynamic<'T>: reference-type IAsyncEnumerable implementation using the dynamic path, with proper cloning support for re-enumeration - TaskSeqBuilder.Run: else-branch now creates TaskSeqDynamic instead of raising - taskSeqDynamic: new CE builder (inherits TaskSeqBuilder) and module value; identical to taskSeq in compiled code, uses dynamic path in FSI - 24 new tests covering: empty, single/multi yield, for/while loops, async bind, Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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Closes #246
Summary
This PR implements the dynamic (FSI-compatible) resumable code path for
taskSeqcomputation expressions, fixing theNotImplementedExceptionthat was raised whenevertaskSeqwas used in F# Interactive or any context where the F# compiler cannot emit static resumable code.Root Cause
The
TaskSeqBuilder.Runmethod has two branches controlled by__useResumableCode:__stateMachineto generate a static state machine structNotImplementedExceptionFix
New types added
TaskSeqDynamicInfo<'T>ResumptionDynamicInfosubclass. OverridesMoveNextto drive the resumption function and handle yield/await/completion—same logic as the staticMoveNextMethodImpl.TaskSeqDynamic<'T>IAsyncEnumerable<'T>implementation for the dynamic path. Stores_initialResumptionFuncinstead of a compiler-generated machine struct, with correct cloning for re-enumeration.Builder changes
TaskSeqBuilder.Runelsebranch now creates aTaskSeqDynamic<'T>instead of raising.TaskSeqDynamicBuildertype (inheritsTaskSeqBuilderwith no overrides—the baseRunalready handles both paths).taskSeqDynamicCE value exported fromTaskSeqDynamicBuildermodule.Suppression
#nowarn "3513"added toTaskSeqBuilder.fs—theResumableCode.Invokecall in the dynamicelsebranch is an intentional use of resumable code as a regular delegate.Trade-offs
TaskSeqDynamic<'T>) vs. the static path's struct. This is acceptable since the dynamic path is only used in FSI.taskSeqDynamicis functionally identical totaskSeqin compiled code (uses the same static path). Its only advantage overtaskSeqis that it documents intent for code meant to run in FSI.Test Status
✅ Build: 0 warnings, 0 errors (Release)
✅ Fantomas: formatting check passes
✅ Tests: 5093 passed (24 new + 5069 existing), 2 skipped, 0 failed
New tests cover: empty sequence, single/multi yield,
for/whileloops,Task/Asyncbind,yield!fromseq/taskSeq/taskSeqDynamic,tryWith,tryFinally,use, cancellation, re-enumeration, large sequences, nested loops.