Clarify transmute example #122990
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Clarify transmute example #122990
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…pratt Clarify transmute example The example claims using an iterator will copy the entire vector, but this is not true in practice thanks to internal specializations in the stdlib (see https://godbolt.org/z/cnxo3MYs5 for confirmation that this doesn't reallocate nor iterate over the vec's elements). Since neither the copy nor the optimization is guaranteed I opted for saying that they _may_ happen.
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…iaskrgr Rollup of 8 pull requests Successful merges: - rust-lang#122802 (Provide structured suggestion for unconstrained generic constant) - rust-lang#122858 (Tweak `parse_dot_suffix_expr`) - rust-lang#122923 (In `pretty_print_type()`, print `async fn` futures' paths instead of spans.) - rust-lang#122990 (Clarify transmute example) - rust-lang#122995 (Clean up unnecessary headers/flags in coverage mir-opt tests) - rust-lang#123003 (CFI: Handle dyn with no principal) - rust-lang#123005 (CFI: Support complex receivers) - rust-lang#123020 (Temporarily remove nnethercote from the review rotation.) r? `@ghost` `@rustbot` modify labels: rollup
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…pratt Clarify transmute example The example claims using an iterator will copy the entire vector, but this is not true in practice thanks to internal specializations in the stdlib (see https://godbolt.org/z/cnxo3MYs5 for confirmation that this doesn't reallocate nor iterate over the vec's elements). Since neither the copy nor the optimization is guaranteed I opted for saying that they _may_ happen.
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…iaskrgr Rollup of 8 pull requests Successful merges: - rust-lang#120557 (Add rust-lldb pretty printing for Path and PathBuf) - rust-lang#122802 (Provide structured suggestion for unconstrained generic constant) - rust-lang#122858 (Tweak `parse_dot_suffix_expr`) - rust-lang#122990 (Clarify transmute example) - rust-lang#122995 (Clean up unnecessary headers/flags in coverage mir-opt tests) - rust-lang#123003 (CFI: Handle dyn with no principal) - rust-lang#123005 (CFI: Support complex receivers) - rust-lang#123020 (Temporarily remove nnethercote from the review rotation.) r? `@ghost` `@rustbot` modify labels: rollup
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Mar 25, 2024
…iaskrgr Rollup of 8 pull requests Successful merges: - rust-lang#120557 (Add rust-lldb pretty printing for Path and PathBuf) - rust-lang#122802 (Provide structured suggestion for unconstrained generic constant) - rust-lang#122858 (Tweak `parse_dot_suffix_expr`) - rust-lang#122990 (Clarify transmute example) - rust-lang#122995 (Clean up unnecessary headers/flags in coverage mir-opt tests) - rust-lang#123003 (CFI: Handle dyn with no principal) - rust-lang#123005 (CFI: Support complex receivers) - rust-lang#123020 (Temporarily remove nnethercote from the review rotation.) r? `@ghost` `@rustbot` modify labels: rollup
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…iaskrgr Rollup of 7 pull requests Successful merges: - rust-lang#122858 (Tweak `parse_dot_suffix_expr`) - rust-lang#122982 (Add more comments to the bootstrap code that handles `tests/coverage`) - rust-lang#122990 (Clarify transmute example) - rust-lang#122995 (Clean up unnecessary headers/flags in coverage mir-opt tests) - rust-lang#123003 (CFI: Handle dyn with no principal) - rust-lang#123005 (CFI: Support complex receivers) - rust-lang#123020 (Temporarily remove nnethercote from the review rotation.) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup merge of rust-lang#122990 - SkiFire13:transmute-may-copy, r=jhpratt Clarify transmute example The example claims using an iterator will copy the entire vector, but this is not true in practice thanks to internal specializations in the stdlib (see https://godbolt.org/z/cnxo3MYs5 for confirmation that this doesn't reallocate nor iterate over the vec's elements). Since neither the copy nor the optimization is guaranteed I opted for saying that they _may_ happen.
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The example claims using an iterator will copy the entire vector, but this is not true in practice thanks to internal specializations in the stdlib (see https://godbolt.org/z/cnxo3MYs5 for confirmation that this doesn't reallocate nor iterate over the vec's elements). Since neither the copy nor the optimization is guaranteed I opted for saying that they may happen.