Struct tracing_subscriber::fmt::writer::BoxMakeWriter [−][src]
pub struct BoxMakeWriter { /* fields omitted */ }
This is supported on crate feature
fmt
only.Expand description
A writer that erases the specific io::Write
and Makewriter
types being used.
This is useful in cases where the concrete type of the writer cannot be known until runtime.
Examples
A function that returns a Subscriber
that will write to either stdout or stderr:
fn dynamic_writer(use_stderr: bool) -> impl Subscriber { let writer = if use_stderr { BoxMakeWriter::new(std::io::stderr) } else { BoxMakeWriter::new(std::io::stdout) }; tracing_subscriber::fmt().with_writer(writer).finish() }
Implementations
Constructs a BoxMakeWriter
wrapping a type implementing MakeWriter
.
Trait Implementations
Auto Trait Implementations
impl !RefUnwindSafe for BoxMakeWriter
impl Send for BoxMakeWriter
impl Sync for BoxMakeWriter
impl Unpin for BoxMakeWriter
impl !UnwindSafe for BoxMakeWriter