Understanding $args in PowerShell

chutestrate

That makes sense.

chutestrate

For my current limited understanding arrays are easier to understand than than the $args

scottalanmiller

@chutestrate said:

For my current limited understanding arrays are easier to understand than than the $args

$args is just an array, nothing more.

scottalanmiller

Here is a little array program to do basically the same thing as above but using an array defined inside of the script rather than passing in arguments from the command line...

$myarray = "John", "Peter", "Linda", "Scott", "Norman", "Jenny"

for ($i=0; $i -lt $myarray.length; $i++) {
   'This is $myarray[' + $i + "], which is: " + $myarray[$i]
}

scottalanmiller

When you run it you get this...

> .\arraydemo.ps1
This is $myarray[0], which is: John
This is $myarray[1], which is: Peter
This is $myarray[2], which is: Linda
This is $myarray[3], which is: Scott
This is $myarray[4], which is: Norman
This is $myarray[5], which is: Jenny

chutestrate

@scottalanmiller said:

@chutestrate said:

For my current limited understanding arrays are easier to understand than than the $args

$args is just an array, nothing more.

don't follow that one.

scottalanmiller

So as you can see, I set the array to have those names in it with this line...

$myarray = "John", "Peter", "Linda", "Scott", "Norman", "Jenny"

When you use $args, the exact same thing is happening except that PowerShell is doing it automatically and hidden from you because it is happening from the command line and you don't write it out explicitly. But what is happening under the hood in a case where you do this...

.\myexample John Peter Linda Scott Norman Jenny

What PowerShell is doing without you having to write it is basically this...

$args = "John", "Peter", "Linda", "Scott", "Norman", "Jenny"

scottalanmiller

@chutestrate said:

$args is just an array, nothing more.

don't follow that one.

Not sure what else to say. It's that simple. $args is an array. $myarray is an array. There's nothing more to it. The only thing that makes $args special is that it is the one array that PowerShell makes for you when you run your script.

chutestrate

Not a problem. This has been phenomenal. I've learned a lot. I'll try to use this to understand the args. Unfortunately, I'm looping back to some of my original confusion. I know you addressed it, but it's not making completed sense.

scottalanmiller

Definitely leave $args for now and focus on arrays. Once you are solid on arrays, $args is pretty much self explanatory. Try doing some sample scripting with arrays for things. That will help a lot. In all seriousness, doing a MadLibs script is a good way to learn.

chutestrate

I'll do that.

scottalanmiller

I doubt that Martin will agree but I don't find PowerShell to be particularly well suited to learning programming concepts. It's a great language for what it is, but I'm very glad that I learned programming on other languages and then learning PowerShell.

chutestrate

I'm not fooling myself. I don't do well with trying to be a programmer. This is part of the testing goals. I just got interested in powershell, and am trying it out. Thank you for all the time. I'm rereading the posts, and I'm going to have a hard time matching $args to arrays. Maybe tomorrow it will click.

scottalanmiller

@chutestrate said:

I'm rereading the posts, and I'm going to have a hard time matching $args to arrays. Maybe tomorrow it will click.

Just remember that there is nothing to match. $args is just another array like any other. It's not a different thing. It's not "like" an array, or similar to or anything. It is an array. $args is the name of an array. I have a feeling that you are thinking of $args as a thing rather than the name of an array.

chutestrate

I definitely am. Unfortunately, i don't see it the way you are telling me.

Martin9700

@scottalanmiller said:

I doubt that Martin will agree but I don't find PowerShell to be particularly well suited to learning programming concepts. It's a great language for what it is, but I'm very glad that I learned programming on other languages and then learning PowerShell.

The languages I've mostly worked with are batch/cmd, Visual Basic, vbScript and PowerShell. So PowerShell is a vast improvement over those

It took me awhile to really grasp the idea of objects and using them for everything in PowerShell, but once I did the whole language opened up to me and I began to realize all the things I could do.

chutestrate

Both of you have been immensely helpful. I hope I can return the favor in some way.

scottalanmiller

@Martin9700 said:

@scottalanmiller said:

I doubt that Martin will agree but I don't find PowerShell to be particularly well suited to learning programming concepts. It's a great language for what it is, but I'm very glad that I learned programming on other languages and then learning PowerShell.

The languages I've mostly worked with are batch/cmd, Visual Basic, vbScript and PowerShell. So PowerShell is a vast improvement over those

It took me awhile to really grasp the idea of objects and using them for everything in PowerShell, but once I did the whole language opened up to me and I began to realize all the things I could do.

I come at it from the other direction. Was doing C and Fortran, then Java and C#. Everything is better than Fortran, though.

scottalanmiller

@chutestrate said:

I definitely am. Unfortunately, i don't see it the way you are telling me.

If I could figure out how you are perceiving it then maybe I could help more. I'm not sure how you are looking at it, though, which makes it hard for me.

chutestrate

Trying to sort it out. The automation piece is part of it. If it's created automatically why is the programmer designating what $args[0], [1], [2], etc is.