Struct BuildEnv

pub struct BuildEnv { /* private fields */ }

Allow retrieval of values pretaining to a build process that may be related to the target and/or host triple.

Implementations

impl BuildEnv

pub fn from_env() -> Result<BuildEnv, VarError<String>>

Use environment variables (such as those set by cargo) to determine values for target and host via the environment variables TARGET and HOST.

pub fn new_cross(host: String, target: String) -> BuildEnv

Construct a BuildEnv where the host and target may be different.

pub fn new(trip: String) -> BuildEnv

Construct a BuildEnv where target and host are the same.

pub fn target(&self) -> &str

The target we’re supplying values for

pub fn host(&self) -> &str

The host we’re supplying values for

pub fn used_env_vars(&self) -> impl Iterator<Item = &OsString>

Get the env vars that have been used by build-env queries so far

pub fn cargo_print_used_env_vars(&self)

Print the used environment variables in the form interpreted by cargo: cargo:rerun-if-env-changed=FOO

pub fn mark_used(&mut self, var: OsString)

pub fn var<K: AsRef<OsStr>>(&mut self, var_base: K) -> Option<OsString>

Query the environment for a value, trying the most specific first, before querying more general variables.

1. <var>_<target> - for example, CC_x86_64-unknown-linux-gnu
2. <var>_<target_with_underscores> - for example, CC_x86_64_unknown_linux_gnu
3. <build-kind>_<var> - for example, HOST_CC or TARGET_CFLAGS
4. <var> - a plain CC, AR as above.

pub fn var_str<K: AsRef<OsStr> + Debug + Any>( &mut self, var_base: K, ) -> Option<Result<String, VarError<K>>>

The same as [var()], but converts the return to an OsString and provides a useful error message

Trait Implementations

impl Clone for BuildEnv

fn clone(&self) -> BuildEnv

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for BuildEnv

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.