rust-cargo

问题 I have a crate that is imported straight off of GitHub, as per Cargo's documentation: [dependencies] libfoo = { git = "ssh://git@github.com/me/libfoo", branch = "dev" } [lib] path = "src/rust/lib.rs" name = "myprj" crate-type = ["cdylib"] Running cargo build works fine here, Cargo fetches libfoo and builds it in the ~/.cargo directory. When I try to use (import) it in lib.rs : extern crate libfoo; //also tried foo Cargo chokes: error[E0463]: can't find crate for `libfoo` --> src/rust/lib.rs:1

问题 I have two projects my_project and my_inner_project in one cargo workspace. They both depend on gfx (and gfx_core and gfx_device_gl). I've found a bug in gfx_device_core, so I've forked it, cloned, patched locally and want to test it before commit. Projects structure: -my_project --my_inner_project ---Cargo.toml --Cargo.toml -gfx --src ---core ----Cargo.toml #package gfx_core ---backend ----gl -----Cargo.toml #package gfx_device_gl ---render ----Cargo.toml #package gfx --Cargo.toml Now I want

问题 If I define a dependency like foo = { version = "1.0.0", optional = true } , will it be available when I do "cargo run"? Can I check if it is enabled in the code? if cfg!(feature = "foo") {} Doesn't seem to be working, like the feature is missing all the time. 回答1: Moving answer to 60258216 here: Optional dependencies do double as features: https://stackoverflow.com/a/39759592/8182118 They will not be enabled by default unless they're listed in the default feature, though you can enable the

问题 If I define a dependency like foo = { version = "1.0.0", optional = true } , will it be available when I do "cargo run"? Can I check if it is enabled in the code? if cfg!(feature = "foo") {} Doesn't seem to be working, like the feature is missing all the time. 回答1: Moving answer to 60258216 here: Optional dependencies do double as features: https://stackoverflow.com/a/39759592/8182118 They will not be enabled by default unless they're listed in the default feature, though you can enable the

问题 The Cargo FAQ states that Cargo.lock is not used for libraries, instead using dependency version ranges found in Cargo.toml , to reduce lib duplication among shared dependencies. However, I think there are instances where using a known successful build of a lib dependency is preferable. Namely, when a dependency no longer builds due to updates of its own dependencies. Is it possible to configure Cargo to favour a library's Cargo.lock , over Cargo.toml , if it's available? Preferably on a by

问题 The Cargo FAQ states that Cargo.lock is not used for libraries, instead using dependency version ranges found in Cargo.toml , to reduce lib duplication among shared dependencies. However, I think there are instances where using a known successful build of a lib dependency is preferable. Namely, when a dependency no longer builds due to updates of its own dependencies. Is it possible to configure Cargo to favour a library's Cargo.lock , over Cargo.toml , if it's available? Preferably on a by

问题 I'm writing a Cargo helper command that needs to know the default target triple used by Rust/Cargo (which I presume is the same as host's target triple). Ideally it should be a compile-time constant. There's ARCH constant, but it's not a full triple. For example, it doesn't distinguish between soft float and hard float ARM ABIs. env!("TARGET") would be ideal, but it's set only for build scripts, and not the lib/bin targets. I could pass it on to the lib with build.rs and dynamic source code

问题 I'm stuck when learning how to access a module. I'm trying to insert a folder other than src into src . It's not working and it gives me an error. Here this is my project tree. $ Project1 . |-- src | |-- main.rs | |--FolderinSrcFolder | |--folderinsrcmodule.rs | |--anothersrc | |--mod.rs | |-- rootmodule.rs |-- Cargo.toml |-- Cargo.lock How can I access anothersrc/mod.rs src/main.rs ? How can I access rootmodule.rs from src/main.rs ? I already read the Rust documentation. 回答1: Don't . Put all

问题 I have a simple project using the Solicit example to make a request with HTTPS. My Cargo.toml has: [package] name = "test" version = "0.1.0" authors = ["einchear"] [dependencies.openssl] version = "0.7.14" features = ["tlsv1_2", "npn"] [dependencies.solicit] version = "0.4.4" features = ["tls"] When I tried to run cargo build , the error is: error: Package `openssl v0.9.12` does not have these features: `npn, tlsv1_2` Why 0.9.12 instead 0.7.14? 回答1: Solicit hasn't released a new version in

问题 Is there a standard way to determine what features are available for a given crate? I'm trying to read Postgres timezones, and this says to use the crate postgres = "0.17.0-alpha.1" crate's with-time or with-chrono features. When I try this in my Cargo.toml: [dependencies] postgres = { version = "0.17.0-alpha.1", features = ["with-time"] } I get this error: error: failed to select a version for `postgres`. ... required by package `mypackage v0.1.0 (/Users/me/repos/mypackage)` versions that