Hi,

this is my code for /bin/bash:

function removeFirstSubstring {
tempVar=${1/$2/""}
echo $tempVar
}

var="one -two three -four five"
var=$(removeFirstSubstring "$var" "-two * ")
echo $var

I want to have the output "one -four five". At the moment it only gives me "one five" though.

Can you help me?

Thank you in advance!

Your "-two *" is expanding to -two followed by a list of everything in the current folder. The results in a user function or bash internal function will depend upon what is in the folder, which is not optimal in this case. If you replace with you may get the desired output.

You do not say, but I infer that you are attempting to get a match to two strings, one fixed and one regex, in the same parameter. Can you confirm or contradict this inference?

Getting something CLOSE to what I did infer would be using single quotes instead of double quotes to delimit that parameter. In this case you would NOT get what you want, since the * would match ALL the remaining string rather than just the next word. Think about that a bit, and you may see a few possible solutions. (None of which will matter if my inference is false.)

I look forward to seeing your reply.

Actually it's not because it's in double-quotes on the function call, and when it gets used within the ${1/$2/} expansion it is treated as a pattern rather than filename expansion.

The problem is simply that the '*' character matches zero or more of any character (including space) which is why it doesn't give him the result he wants.

If what he actually wants is to match to the end of the word then he'll need to enable the extglob shell option (shopt -s extglob) and use +([^ ]) instead of '*' as the pattern.

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