This blog is by no means to say that I have mastered it but I think that I finally understood why I could not learn the powershell. I think that is because I approached powershell from my bash scripting experience. What do I mean by it? When we use bash shell, we work with string but when we work with powershell, that does not work well. Powershell always returns objects not string and hence when we want to process output of certain output, it is necessary that we approach it from this perspective. So let me illustrate this.
Often times we want to list something and then 'grep' certain words from the list output. For instance, let us try 'alias' command on powershell.
Alias command produces lots of output that its output is more than a page. So probably I want to see if alias output has the line that contains the word 'content' in some easy way. Readily I think of 'grep' command and I remember that select-string works somewhat similarly. So let us try Select-String.
Hmm. Nothing... But I know that there is a line that has the word 'content' What's going on here? Apparently, Select-String is only looking for words to match from Name column. So let us now try 'asnp' to verify it.
Ok, that is better but I want to get the entire line. What should I do?
This is where I realized that powershell works on objects not string. In principle, powershell operates on objects and hence when the powershell returns the output for alias command, it actually returned the list of objects. So if we want to get the whole line which in this case is an object, we want to try to match the entire object. Here is the trick.
Yes, we got what we wanted. Again, this is because we were looking for object where its definition contains 'content' and it returns the list of those object.
In summary, powershell operates on objects so when you use powershell, keep that in mind!
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