@zkochan/pnpm
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A fast implementation of npm install
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JavaScript
/**
* Module dependencies.
*/
var now = require('date-now');
/**
* Returns a function, that, as long as it continues to be invoked, will not
* be triggered. The function will be called after it stops being called for
* N milliseconds. If `immediate` is passed, trigger the function on the
* leading edge, instead of the trailing.
*
* @source underscore.js
* @see http://unscriptable.com/2009/03/20/debouncing-javascript-methods/
* @param {Function} function to wrap
* @param {Number} timeout in ms (`100`)
* @param {Boolean} whether to execute at the beginning (`false`)
* @api public
*/
module.exports = function debounce(func, wait, immediate){
var timeout, args, context, timestamp, result;
if (null == wait) wait = 100;
function later() {
var last = now() - timestamp;
if (last < wait && last > 0) {
timeout = setTimeout(later, wait - last);
} else {
timeout = null;
if (!immediate) {
result = func.apply(context, args);
if (!timeout) context = args = null;
}
}
};
return function debounced() {
context = this;
args = arguments;
timestamp = now();
var callNow = immediate && !timeout;
if (!timeout) timeout = setTimeout(later, wait);
if (callNow) {
result = func.apply(context, args);
context = args = null;
}
return result;
};
};