DZone Snippets: Phrogz's Code Snippets

Splitting/Joining URLs

Phrogz (Gavin Kistner) — Fri, 29 Apr 2005 22:04:55 GMT

File.dirname "http://foo.com/bar/stuff.html"

#=> "http://foo.com/bar"



File.basename "http://foo.com/bar/stuff.html"

#=> "stuff.html"



File.split "http://foo.com/bar/stuff.html"

#=> ["http://foo.com/bar", "stuff.html"]



File.join( File.dirname("http://foo.com/bar/doc.html"), "relative_link.html" )

# => "http://foo.com/bar/relative_link.html"

(Originally by Ilmari Heikkinen on the ruby-talk mailing list.)

Loop through an array without wasteful lookups

Phrogz (Gavin Kistner) — Sun, 03 Apr 2005 06:29:18 GMT

Looking up the length of an array on each iteration of a loop is slow and inefficient (if the length of the array isn't changing).

If it's OK to iterate from back to front:

for ( var i=myArray.length-1; i>=0; --i ){

  ...

}

If you need to go from front to back:

for ( var i=0, len=myArray.length; i  ...

}

Add a JS function for bounded random numbers

Phrogz (Gavin Kistner) — Sun, 03 Apr 2005 06:13:12 GMT

Math.randomMax = function(maxVal,asFloat){

	var val = Math.random()*maxVal;

	return asFloat?val:Math.round(val);

}

For a random integer between 0 and 10 (inclusive), simply:
var theNumber = Math.randomMax( 10 );

For a random float value between 0 and 10, pass a truth value to the second parameter:
var theNumber = Math.randomMax( 10, true );