Macro gauge 

macro_rules! gauge {
    ($name:literal = $value:expr $(, $tag:ident = $tv:expr)* $(,)?) => { ... };
    ($name:literal += $value:expr $(, $tag:ident = $tv:expr)* $(,)?) => { ... };
    ($name:literal -= $value:expr $(, $tag:ident = $tv:expr)* $(,)?) => { ... };
}

Sets, increments, or decrements a gauge metric.

Syntax

use objectstore_metrics::gauge;

gauge!("runtime.num_workers" = 4usize);
gauge!("connections" += 1usize);
gauge!("connections" -= 1usize);
gauge!("runtime.num_workers" = 4usize, pool = "default");

Values are converted to f64 via AsF64. Supported types include f64, Duration, integer primitives, u64, and usize.

Tag keys are identifiers; tag values must implement Into<SharedString>.