Crate vlog [−] [src]

vlog

Macros to do stdout / stderr logs based on verbosity level.

Useful for CLI applications. The default verbosity level is 0, and the supported max verbosity level is 3, which is equivalent to -vvv flags seen in most Linux CLI applications.

Example

#[macro_use]
extern crate vlog;

use vlog::{get_verbosity_level, set_verbosity_level};

fn main() {
    // default verbosity level is 0
    assert_eq!(0, get_verbosity_level());

    v0!("v0 stdout prints");
    v1!("v1 stdout won't print");
    v2!("v2 stdout won't print");
    v3!("v3 stdout won't print");

    // set custom verbosity level
    set_verbosity_level(1);
    assert_eq!(1, get_verbosity_level());

    v0!("{} stdout prints", "v0");
    v1!("{} stdout prints", "v1");
    v2!("{} stdout won't print", "v2");
    v3!("{} stdout won't print", "v3");

    // set custom max verbosity level
    set_verbosity_level(3);
    assert_eq!(3, get_verbosity_level());

    v0!("{} stdout prints", "v0");
    v1!("{} stdout prints", "v1");
    v2!("{} stdout prints", "v2");
    v3!("{} stdout prints", "v3");

    // stderr macros also available
    ve0!("{} stderr prints", "ve0");
    ve1!("{} stderr prints", "ve1");
    ve2!("{} stderr prints", "ve2");
    ve3!("{} stderr prints", "ve3");
}

Macros

v0	Always prints to `stdout`. Follows `format!` style.
v1	Prints to `stdout` if verbosity level is >= 1. Follows `format!` style.
v2	Prints to `stdout` if verbosity level is >= 2. Follows `format!` style.
v3	Prints to `stdout` if verbosity level is >= 3. Follows `format!` style.
ve0	Always prints to `stderr`. Follows `format!` style.
ve1	Prints to `stderr` if verbosity level is >= 1. Follows `format!` style.
ve2	Prints to `stderr` if verbosity level is >= 2. Follows `format!` style.
ve3	Prints to `stderr` if verbosity level is >= 3. Follows `format!` style.
verbose_elog	Common macro for verbose `stderr` logs. This is meant to be used internally only.
verbose_log	Common macro for verbose `stdout` logs. This is meant to be used internally only.

Functions

get_verbosity_level	Gets the application verbosity level atomically. This method is thread-safe.
set_verbosity_level	Sets the application verbosity level atomically. This method is thread-safe.