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

Formats the value using the given formatter. Read more

The concrete io::Write implementation returned by make_writer. Read more

Returns an instance of Writer. Read more

Returns a Writer for writing data from the span or event described by the provided Metadata. Read more

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

Performs the conversion.

Instruments this type with the provided Span, returning an Instrumented wrapper. Read more

Instruments this type with the current Span, returning an Instrumented wrapper. Read more

Performs the conversion.

This is supported on crate feature fmt only.

Wraps self and returns a MakeWriter that will only write output for events at or below the provided verbosity Level. For instance, Level::TRACE is considered to be _more verbosethanLevel::INFO`. Read more

This is supported on crate feature fmt only.

Wraps self and returns a MakeWriter that will only write output for events at or above the provided verbosity Level. Read more

This is supported on crate feature fmt only.

Wraps self with a predicate that takes a span or event’s Metadata and returns a bool. The returned MakeWriter’s MakeWriter::make_writer_for method will check the predicate to determine if a writer should be produced for a given span or event. Read more

This is supported on crate feature fmt only.

Combines self with another type implementing MakeWriter, returning a new MakeWriter that produces writers that write to both outputs. Read more

This is supported on crate feature fmt only.

Combines self with another type implementing MakeWriter, returning a new MakeWriter that calls other’s make_writer if self’s make_writer returns OptionalWriter::none. Read more

The type returned in the event of a conversion error.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.

Attaches the provided Subscriber to this type, returning a WithDispatch wrapper. Read more

Attaches the current default Subscriber to this type, returning a WithDispatch wrapper. Read more