A lightweight logging library exploring a new paradigm for handling excluded logs. It's use is designed for both application developers and library developers. Optional chaining syntax is used to handle excluding logs, allowing for more efficient logging, especially when dealing with expensive to compute log messages. The log level is set once at the beginning of the application via an environment variable and cannot be changed during runtime. The default log level for jsr:@doctor/log/app is info and the default log level for jsr:@doctor/log/lib is none. If the environment variable is not set; set to an invalid value; or permissions to read the variable is not granted from the start, this library will fall back to its default log level. This library makes use of the Temporal API so the --unstable-temporal flag is required at the time of writing this.

LOG_LEVEL=4 deno run -E='LOG_LEVEL' --unstable-temporal main.ts

import { terminal } from "@doctor/log/app";

terminal.info?.("Hello World!");
// ~[TIMESTAMP] [INFO] Hello World!

ABC_XYZ=4 deno run -E='ABC_XYZ' --unstable-temporal lib.ts

import { createTerminal } from "@doctor/log/lib";

const terminal = await createTerminal("my-app", "ABC_XYZ");
terminal.info?.("Hello World!");
// ~[TIMESTAMP] [INFO] [my-app] Hello World!