BitLogger/docs/api/logger-with-min-level.md

name, group, category, update-time, description, key-word

name	group	category	update-time	description	key-word
logger-with-min-level	api	logging	20260512	Replace the logger minimum enabled level so lower-severity records are skipped earlier.	logger level filter public

Logger-with-min-level

Replace the logger's minimum enabled level. This API controls the first gate checked by log(...) and the convenience level methods.

Interface

pub fn[S] Logger::with_min_level(self : Logger[S], min_level : Level) -> Logger[S] {}

input

• self : Logger[S] - Base logger whose level threshold should change.
• min_level : Level - New minimum enabled level.

output

• Logger[S] - A new logger value carrying the updated threshold.

Explanation

Detailed rules explaining key parameters and behaviors

• log(...) checks is_enabled(level) before constructing and writing a record.
• Lower-severity records below min_level are skipped without reaching the sink.
• The returned logger is derived from self; the original logger value is not mutated.
• This API replaces the stored threshold and does not add a wrapper sink.
• Only min_level changes. Sink, target, and timestamp behavior stay on the same Logger[S] surface.

How to Use

Here are some specific examples provided.

When Raise Noise Floor In Production

When only warning and error records should be emitted:

let logger = Logger::new(console_sink())
  .with_min_level(Level::Warn)

In this example, trace, debug, and info calls are skipped.

The returned logger still uses the same ordinary synchronous logging calls; only the severity gate changes.

When Derive A More Verbose Local Logger

When one branch of code should keep a different threshold:

let base = Logger::new(console_sink(), min_level=Level::Info)
let debug_logger = base.with_min_level(Level::Debug)

In this example, the sink is reused while the threshold changes per logger value.

Error Case

e.g.:

• If min_level is set too high, expected lower-severity diagnostics may disappear.

• If callers need richer predicate logic than a simple threshold, with_filter(...) should be used instead.

Notes

1. This API skips disabled levels before any sink write happens.

2. Use it before adding more complex predicate-based filtering rules.

3. Use a derived logger value when one branch should tighten the threshold and the base logger should keep its broader level gate.