mirror of https://github.com/rust-lang/rfcs
58 lines
1.5 KiB
Markdown
58 lines
1.5 KiB
Markdown
- Feature Name: main_reexport
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- Start Date: 2015-08-19
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- RFC PR: https://github.com/rust-lang/rfcs/pull/1260
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- Rust Issue: https://github.com/rust-lang/rust/issues/28937
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# Summary
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Allow a re-export of a function as entry point `main`.
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# Motivation
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Functions and re-exports of functions usually behave the same way, but they do
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not for the program entry point `main`. This RFC aims to fix this inconsistency.
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The above mentioned inconsistency means that e.g. you currently cannot use a
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library's exported function as your main function.
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Example:
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pub mod foo {
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pub fn bar() {
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println!("Hello world!");
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}
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}
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use foo::bar as main;
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Example 2:
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extern crate main_functions;
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pub use main_functions::rmdir as main;
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See also https://github.com/rust-lang/rust/issues/27640 for the corresponding
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issue discussion.
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The `#[main]` attribute can also be used to change the entry point of the
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generated binary. This is largely irrelevant for this RFC as this RFC tries to
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fix an inconsistency with re-exports and directly defined functions.
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Nevertheless, it can be pointed out that the `#[main]` attribute does not cover
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all the above-mentioned use cases.
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# Detailed design
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Use the symbol `main` at the top-level of a crate that is compiled as a program
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(`--crate-type=bin`) – instead of explicitly only accepting directly-defined
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functions, also allow (possibly non-`pub`) re-exports.
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# Drawbacks
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None.
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# Alternatives
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None.
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# Unresolved questions
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None.
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