small iter.intersperse.fold() optimization #142549
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No need to call into fold when the first item is already None, this avoids some redundant work for empty iterators. "But it uses Fuse" one might want to protest, but Fuse is specialized and may call into the inner iterator anyway.
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…tgross35 small iter.intersperse.fold() optimization No need to call into fold when the first item is already None, this avoids some redundant work for empty iterators. "But it uses Fuse" one might want to protest, but Fuse is specialized and may call into the inner iterator anyway.
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Rollup of 17 pull requests Successful merges: - #124595 (Suggest cloning `Arc` moved into closure) - #139594 (Simplify `ObligationCauseCode::IfExpression`) - #141311 (make `tidy-alphabetical` use a natural sort) - #141648 ([rustdoc] Do not emit redundant_explicit_links lint if the doc comment comes from expansion) - #142255 (Add edition checks for some tests that had divergent output) - #142285 (tests: Do not run afoul of asm.validity.non-exhaustive in input-stats) - #142549 (small iter.intersperse.fold() optimization) - #142637 (Remove some glob imports from the type system) - #142647 ([perf] Compute hard errors without diagnostics in impl_intersection_has_impossible_obligation) - #142700 (Remove incorrect comments in `Weak`) - #142884 (StableMIR: Add method to retrieve body of coroutine) - #142925 (Rewrite `.gitattributes` CRLF ui tests into run-make tests) - #143001 (Rename run always ) - #143010 (Update `browser-ui-test` version to `0.20.7`) - #143015 (Add `sym::macro_pin` diagnostic item for `core::pin::pin!()`) - #143020 (codegen_fn_attrs: make comment more precise) - #143033 (Expand const-stabilized API links in relnotes) r? `@ghost` `@rustbot` modify labels: rollup
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…tgross35 small iter.intersperse.fold() optimization No need to call into fold when the first item is already None, this avoids some redundant work for empty iterators. "But it uses Fuse" one might want to protest, but Fuse is specialized and may call into the inner iterator anyway.
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…tgross35 small iter.intersperse.fold() optimization No need to call into fold when the first item is already None, this avoids some redundant work for empty iterators. "But it uses Fuse" one might want to protest, but Fuse is specialized and may call into the inner iterator anyway.
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…rors Rollup of 18 pull requests Successful merges: - #137843 (make RefCell unstably const) - #140942 (const-eval: allow constants to refer to mutable/external memory, but reject such constants as patterns) - #142549 (small iter.intersperse.fold() optimization) - #142637 (Remove some glob imports from the type system) - #142647 ([perf] Compute hard errors without diagnostics in impl_intersection_has_impossible_obligation) - #142700 (Remove incorrect comments in `Weak`) - #142927 (Add note to `find_const_ty_from_env`) - #142967 (Fix RwLock::try_write documentation for WouldBlock condition) - #142986 (Port `#[export_name]` to the new attribute parsing infrastructure) - #143001 (Rename run always ) - #143010 (Update `browser-ui-test` version to `0.20.7`) - #143015 (Add `sym::macro_pin` diagnostic item for `core::pin::pin!()`) - #143033 (Expand const-stabilized API links in relnotes) - #143041 (Remove cache for citool) - #143056 (Move an ACE test out of the GCI directory) - #143059 (Fix 1.88 relnotes) - #143067 (Tracking issue number for `iter_macro`) - #143073 (Fix some fixmes that were waiting for let chains) Failed merges: - #143020 (codegen_fn_attrs: make comment more precise) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup merge of #142549 - the8472:intersperse-fold-tweak, r=tgross35 small iter.intersperse.fold() optimization No need to call into fold when the first item is already None, this avoids some redundant work for empty iterators. "But it uses Fuse" one might want to protest, but Fuse is specialized and may call into the inner iterator anyway.
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No need to call into fold when the first item is already None, this avoids some redundant work for empty iterators.
"But it uses Fuse" one might want to protest, but Fuse is specialized and may call into the inner iterator anyway.