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Rules with using double parentheses in Bash

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# 8  
Old 02-09-2011
@cfajohnson
Please tell me how you would deal with the 10th 11th and 12th parameter to the Shell script?
Is $1 unambiguous in every context in a Shell script? This is a rhetorical question because I know that you know the answer.
${1} is totally unambiguous.
Whether or not it it is strictly necessary in the context of that particular statement.


Btw. this sort of interchange between professionals is fun and I enjoy it.


Quote:
If you don't know what is required and what is not, how do you now what difference extra "precautions" will make?
The specification does not matter. If you write paranoid scripts which assume that the parameters and data may not conform to specification they will be much more robust when the bad data comes.
Last edited by methyl; 02-09-2011 at 07:48 PM.. Reason: Clarified questioneer.
# 9  
Old 02-09-2011
Quote:
Originally Posted by methyl
@cfajohnson
Please tell me how you would deal with the 10th 11th and 12th parameter to the Shell script?

In the standard manner:
Code:
p10=${10}
p11=${11}
p12=${11}

Quote:
Is $1 unambiguous?

Yes.
Quote:
${1} is totally unambiguous.

As is:
Code:
var=$1

...which is not unnecessarily verbose.
Last edited by cfajohnson; 02-09-2011 at 07:58 PM..
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