Bashscripts.org

I have the following script (put together as an example) that I'm trying to get working but I'm not sure it can be done.



I know that I could simply have put the wdir assignment in the for loop which I did originally but, to make the script as easy to read as possible I'd like to assign all user changing variabes at the top... It's like a template string that I need to have expanded upon execution.

Can this be done or am I dreaming in bash?

Of COURSE it can be done! It's just a matter of figuring out the way that works best for you

You could try something with sed, like this:


OR like you mentioned, you could set the $wdir variable in the loop, but use a prefix and suffix that you set at the top of the script. Something like this:


I hope this helps! There are probably dozens of other ways that would work too!

I don't really get the point of doing that.

If you want to make the script as easy to read as possible, then just define your variable at the
top of your script ( i.e., wdir= ) and write a comment telling what it does. Then, in your case,
define wdir directly in the for loop.

Also, for is used to iterate arguments, not strings, neither outputs.
Since you're using bash(1), you can use an array, i.e., envs=(dev stage prod shared).



And as pointed out jeo, if you really want to do that, then define wdir with a default
env string, and replace it in the loop.

OK. What is there to iterate strings and outputs, then?

Thanks jeo - you're solution worked perfectly

Glad to be of service!

You use an array to iterate strings and a while loop with read(0) to iterate commands output.



If you're writing POSIX sh(1), then you'd have to use set(0), a pipe, and a subshell ( if your loop is large ) to read commands output.

well, if I have a space separated list of (spaceless!) items, why should I first make an array of this list and then iterate through that array
instead of just like in good old times iterate through that list ?





this WORKS and is FASTER - not that much, but you know how I am eager to save time

You should do it to make it safer.

Of course, if you know your "list" content it's pointless, but it's a good habit to have.

not much safer

sorry, I should have been more rigorous :

but of course you're right : arrays are basically safer and must be used if you're not sure that each item in the list will not collide with the aimed result. Just : sometimes you can be sure.