I have a string which has a number in it that I would like to replace with another number.
ie
blah blah 32 blah blah<
Many jQuery methods like .text()
can accept a function that returns the value to insert.
Try it out: http://jsfiddle.net/6mBeQ/
$('#my_link').text( function(i,txt) {return txt.replace(/\d+/,'other value'); });
This removes the need to run the selector twice.
Also, when you are getting an element by its ID, it is actually a little quicker if you do not include the tag name.
So instead of
$('a#my_link')
it is better to do
$('#my_link')
as I did above.