Print a warning exactly once during development. Suitable for deprecation warnings, warnings for missing setup etc.
Open a Terminal in the project root and run:
npm install warn-once
The warnOnce function accepts a condition as the first argument. If the condition is true, then it'll print a warning:
const warnOnce = require('warn-once');
// ...
warnOnce(someCondition, 'This is a warning message');
You can call warnOnce multiple times, but if the warning was printed already, it'll not be printed again.
The warning is only shown during development, i.e. if NODE_ENV is not set to 'production'.
FAQs
Show a warning once
We found that warn-once demonstrated a not healthy version release cadence and project activity because the last version was released a year ago. It has 1 open source maintainer collaborating on the project.
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