Document destructors/drop. #128
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matthewjasper
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src/glossory.md
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| ### Initialized | ||
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| A variable is initialized if it has been assigned a value and hasn't since been | ||
| moved from. All other lvalues are assumed to be initialized (only unsafe Rust |
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The parenthetical should just be its own sentence.
src/destructors.md
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| # Destructors | |||
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| When an [intialized] [variable] in Rust goes out of scope or a [temporary] is | |||
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Need a \ before the opening bracket on [variable].
src/destructors.md
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| 2. Recursively running the destructor of all of its fields. | ||
| * The fields of a [struct], [tuple] or [enum variant] are dropped in | ||
| declaration order. \* | ||
| * The elements of an [array] or (owned) [slice][array] are dropped from the |
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Nit: The parenthesis around "owned" aren't needed.
src/destructors.md
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| ## Not running destructors | ||
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| Not running destructors in Rust is safe, so `unsafe` code cannot assume a |
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The entire unsafe middle clause feels unneeded. There's a section devoted to behaviour considered safe that includes leaking memory (though it can be better documented there).
src/destructors.md
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| Not running destructors in Rust is safe, so `unsafe` code cannot assume a | ||
| variable will be dropped, even if it has a type that isn't `'static`. | ||
| [`std::mem::forget`] can be used to avoid running the destructor of a local | ||
| variable. [`std::mem::ManuallyDrop`] provides a wrapper to prevent a field |
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I'd rather this just say that ManuallyDrop provides a convenient wrapper to prevent a variable or field from being dropped automatically. While it's used for avoiding recursive drops, it's used for other reasons as well. E.g. forget actually just puts the value into a ManuallyDrop and then lets Rust drop it without calling the drop method.
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| \* This order was stabilized in [RFC 1857]. | ||
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| Variables are dropped in reverse order of declaration. Variables declared in |
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I think this should be a part of block expressions, but I'm not going to worry about that for this PR.
matthewjasper
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Apparently I don't get a notification when there are new commits. I'll look at this |
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💟 Thanks! And 🙁 sorry for not noticing the second commit sooner. |
cc rust-lang/rust#43034