Today I learned

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Categories

• Javascript
• Mac
• Server

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Javascript

Merge/extend properties of two objects

Similar to jQuery or Underscore extend, but you can do it with pure Javascript.

function extend(a, b) {
	for( var key in b ) { 
		if( b.hasOwnProperty( key ) ) {
			a[key] = b[key];
		}
	}
	return a;
}

Then you use it like this:

var defaults = {validate: false, limit: 5};
var options = {validate: true};

// we extend empty objects so that we do not mutate the defaults object.
var settings = extend({}, defaults);

// If we just want to extend the settings object, we don't need to store into a new variable
extend(settings, options);

// or you can just extend defaults and options directly and save it to settings var.
var settings = extend(defaults, options)

Thanks to Codrops tutorials for this.

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Mac

Keyboard Shortcut to Show/Hide Hidden Files and Folders in Finder

Open Finder, go to any folder and press ⌘ + Shift + . to show/hide hidden files and folders.

Keyboard Shortcut to Open Emoji Insert

On any text editor, press Ctrl + ⌘ + space to open up Emoji & Special Characters window.

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Server

Crontab special keywords

Usually when you create a cronjob, you input something like this:

0 * * * * /command/to/execute

Apparently, there are some special keywords you can use as shortcuts. They are:

• @reboot Run once, at startup.
• @yearly Run once a year, equivalent to 0 0 1 1 *.
• @annually (same as @yearly)
• @monthly Run once a month, equivalent to 0 0 1 * *.
• @weekly Run once a week, equivalent to 0 0 * * 0.
• @daily Run once a day, equivalent to 0 0 * * *.
• @midnight (same as @daily)
• @hourly Run once an hour, equivalent to 0 * * * *.

So you can just type @daily /command/to/execute instead of 0 0 * * * /command/to/execute

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About

This is a collection of stuffs I just learned or came across on the internet that I think are useful.

thoughtbot started this long ago, so credits to them.