It is difficult to just have theoretical knowledge of Reactive extensions and functional programming techniques and not be able to know when it can be used. In order to apply our knowledge, let's take a look at the following scenario.
Let's assume we have to read an Apache log file in an asynchronous manner.
An Apache log line looks like this:
111.222.333.123 HOME - [01/Feb/1998:01:08:39 -0800] "GET /bannerad/ad.htm HTTP/1.0" 200 198 "http://www.referrer.com/bannerad/ba_intro.htm""Mozilla/4.01 (Macintosh; I; PPC)" 111.222.333.123 HOME - [01/Feb/1998:01:08:46 -0800] "GET /bannerad/ad.htm HTTP/1.0" 200 28083 "http://www.referrer.com/bannerad/ba_intro.htm""Mozilla/4.01 (Macintosh; I; PPC)"
Let's dissect the parts of each line.
First, we have the IP address. It has three dots in between some numbers. Second, we have the field that logs the domain of the server.
Third, we have the date and time. Then we get the string, which says what was accessed and...