pub struct Metadata<'a> { /* private fields */ }Expand description
Metadata about a log message.
§Use
Metadata structs are created when users of the library use
logging macros.
They are consumed by implementations of the Log trait in the
enabled method.
Records use Metadata to determine the log message’s severity
and target.
Users should use the log_enabled! macro in their code to avoid
constructing expensive log messages.
§Examples
use log::{Record, Level, Metadata};
struct MyLogger;
impl log::Log for MyLogger {
fn enabled(&self, metadata: &Metadata) -> bool {
metadata.level() <= Level::Info
}
fn log(&self, record: &Record) {
if self.enabled(record.metadata()) {
println!("{} - {}", record.level(), record.args());
}
}
fn flush(&self) {}
}
Implementations§
Trait Implementations§
source§impl<'a> Ord for Metadata<'a>
impl<'a> Ord for Metadata<'a>
1.21.0 · source§fn max(self, other: Self) -> Selfwhere
Self: Sized,
fn max(self, other: Self) -> Selfwhere
Self: Sized,
Compares and returns the maximum of two values. Read more
source§impl<'a> PartialEq for Metadata<'a>
impl<'a> PartialEq for Metadata<'a>
source§impl<'a> PartialOrd for Metadata<'a>
impl<'a> PartialOrd for Metadata<'a>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
This method tests less than or equal to (for
self and other) and is used by the <=
operator. Read moreimpl<'a> Eq for Metadata<'a>
impl<'a> StructuralPartialEq for Metadata<'a>
Auto Trait Implementations§
impl<'a> Freeze for Metadata<'a>
impl<'a> RefUnwindSafe for Metadata<'a>
impl<'a> Send for Metadata<'a>
impl<'a> Sync for Metadata<'a>
impl<'a> Unpin for Metadata<'a>
impl<'a> UnwindSafe for Metadata<'a>
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source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
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Mutably borrows from an owned value. Read more
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Casts the value.
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Casts the value.
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