[Scala 3] @inline def → inline def#871
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…e Function/by-name params Sweep Scala 2 @inline def JVM-optimizer hints to Scala 3 mandatory inline def AST splice across the Opt family (Opt, NOpt, OptArg, OptRef), and mark Function-typed (A => B, (A, B) => C, PartialFunction) parameters as inline to eliminate Function* allocation at call sites. Final shape: - Methods with at least one Function-typed OR by-name parameter: `inline def` with inline-marked Function params. - By-name params (=> T) themselves remain unmarked — `=> T` already provides call-site substitution in Scala 3; `inline (x: => T)` is redundant. Where the by-name was used exactly once in a straight-line if/then/else body, it is reshaped to `(inline x: B)` so the expression is substituted literally (no Function0 thunk allocation). - Trivial accessors (isEmpty/isDefined/nonEmpty/get) kept as plain def to avoid -Xmax-inlines bailout in pattern-match desugaring (`case Opt(x) =>`). - @publicInBinary added on private constructors and referenced private members per Scala 3 inline-body access requirement. - OptArg.argToOptArg preserved as implicit def per slice 3.3 erasure-bridge rationale (untouched). Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Convert jXxx / gXxx adapters that wrap Scala lambdas into Java
functional interfaces to inline def + inline Function param across:
- JFunctionUtils (38/38 inline def + 38/38 inline params; 5 zero-arg
Suppliers reverted via by-name → inline-value where applicable)
- Java8CollectionUtils (9/8)
- GuavaInterop (3/3 — see Future-override exception below)
- ScalaJStream / ScalaJIntStream / ScalaJLongStream / ScalaJDoubleStream
(23/23 + 16/16 ×3)
Eliminates Function* allocation at every jiop call site by splicing the
SAM-conversion at the use site rather than allocating a wrapper.
Future-override exception:
GuavaInterop.ListenableFutureAsScala.{onComplete, transform,
transformWith} are kept as plain def (no inline keyword on def OR
params). They override scala.concurrent.Future methods whose parent
signatures have non-inline params; Scala 3 forbids overriding a
non-inline param with an inline param.
Style:
- Drop trailing `; ()` coercion from Consumer SAM lambdas in
JFunctionUtils — Scala 3 SAM conversion of an Any-returning lambda
to a void-returning Java functional interface accepts the result
directly.
- scalafmt rewraps applied where post-inline insertion exceeded line
width.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Document slice 3.4 outcomes in MIGRATION.md §3: - @inline def → inline def conversion (Opt family + jiop adapters) - Function-typed/by-name parameter inlining - inline def is implicitly final (value-class scope mitigates) - Future-override exception in GuavaInterop (non-inline override constraint) - @publicInBinary applied on private members referenced from inline bodies Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
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… XOps wrappers Marks 49 inline def + 42 inline params across SharedExtensions XOps wrappers, matching fork shape (49/43). Applies on the pre-PR#868 form (class XOps extends AnyVal). The inline keywords will carry into the post-rebase extension blocks since method signatures are preserved by slice 3.1. Methods touched per Ops class: - UniversalOps: |>, applyIf, discard, thenReturn, setup, matchOpt, uncheckedMatch - LazyUniversalOps: evalFuture, evalTry, optIf, optionIf, recoverFrom, recoverToOpt - IntOps: times - FutureOps: onCompleteNow, andThenNow, foreachNow, transformNow (2), transformWithNow, mapNow, flatMapNow, filterNow, collectNow, recoverNow, recoverWithNow, zipWithNow (13 total; wrapToTry/toUnit/toVoid/thenReturn/ignoreFailures kept plain per fork) - OptionOps: forEmpty, mapOr - TryOps: tapFailure - PartialFunctionOps: unless, fold - IterableOnceOps: toMapBy, mkMap, groupToMap, findOpt, flatCollect, collectFirstOpt, reduceOpt, reduceLeftOpt, reduceRightOpt, maxOptBy, minOptBy, indexWhereOpt, asyncFoldLeft, asyncFoldRight, asyncForeach, partitionEither - FutureCompanionOps: eval NoValueMarker / NoValueMarkerFunc unprivatized (referenced from inline def fold body, matches fork). private def it dropped from IterableOnceOps in favor of inline coll.iterator (avoids @publicInBinary on private fwd).
… ObservableExtensions Marks inline def + inline Function/by-name params on AnyVal Ops wrappers in concurrent extensions: - TaskOps: lazyTimeout, tapL, tapErrorL - TaskCompanionOps: traverseOpt, traverseMap, traverseMapValues, usingNow - ObservableOps: findOptL, distinctBy, sortedByL, mkMapL No fork counterpart (these files don't exist on origin/master; project- local extensions). Inline marks applied per project-wide policy for Function-taking and by-name-taking forwarders.
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Rewrites Scala 2
@inline def(JVM optimizer hint) to Scala 3inline def(mandatory compile-time AST splice) across the Opt family AND function-taking ops elsewhere. Closure-eliminating perf win:inline def+inline (f: A => B)parameter usage dropsFunction1allocations at call sites.Scope
Opt family (initial sweep, fork
5fafdbd7)Opt,NOpt,OptArg,OptRef— all@inline def→inline def, with selected by-name params reshaped toinline x: Tfor one-use straight-line cases (getOrElse,orElse,fold(ifEmpty),mapOr(ifEmpty),toRight,toLeft,forEmpty). Trivial accessors (isEmpty/get/toOption/etc.) kept as plaindef—inline defwould re-trigger-Xmax-inlinesbailout on pattern-match desugaring sites.@publicInBinaryadded on private constructors +private[misc]members referenced from inline bodies (Scala 3 ABI requirement).Broader Function-param sweep (fork
a4ddad6b,580625a9,33a5b792,ad505679,ee0be95e)SharedExtensions.scala: 49inline def+ 42inlineparams (matches fork shape 49/43)concurrent/TaskExtensions.scala,concurrent/ObservableExtensions.scala: 11inline def+ 11inlineparamscore/jvm/jiop/{JFunctionUtils, GuavaInterop, Java8CollectionUtils}: closure-taking adapters inlinedcore/jvm/jiop/{ScalaJStream, ScalaJIntStream, ScalaJLongStream, ScalaJDoubleStream}: closure ops inlinedInline-scope rules applied
inline defonly when method has at least one Function-typed (A => B) OR by-name (=> T) param. Pure value-param methods stay plaindef.inlinekeyword stripped from by-name params (inline x: => T→x: => T) — redundant in Scala 3 (=> Talready enables call-site substitution).def(Scala 3 forbids overriding non-inline base method with inline).Whitelist (preserved verbatim — fork keeps these as
@inline)CborInput.scala:56(1 site — tight-loop parser hot path)JsonStringInput.scala(5 sites)RPCFramework.scala(2 sites — RPC dropped from scala-3 in fork)OptArg.argToOptArgpreservation honored per slice 3.3 rationale.Acceptance
git grep '@inline' core/src/main/scala/outside whitelist → 0 hits ✓sbt compile + Test/compile + scalafmtCheckAllgreen ✓@nowarn/-Wconfsuppressions ✓ (one verbatim fork carve-out:@nowarnoninline def discardin SharedExtensions)Source-compat impact
Scala 3
inline defis implicitlyfinal→ cannot be overridden. Downstream subclassers ofOpt/NOpt/OptArg/OptRefwould break, but targets are value classes (finalby construction) — zero impact in practice.SharedExtensionsextension blocks have no inheritance — safe.Translated from fork
origin/mastercommits5fafdbd7(Opt family),a4ddad6b(SharedExtensions),580625a9(JFunctionUtils),33a5b792/ad505679/ee0be95e(ScalaJ*Stream).Slice: 3.4 of Phase 3 (Scala 3 syntax modernization)
Merge order: 3.1 → 3.2 → 3.3 → 3.4
Depends on: #870 (slice 3.3 — must merge first)
Base branch: upstream/scala-3 (not stacked on prior slice)