I was asked to solve a problem at work so I tried to make it as short possible.

Problem:

Read and Modify a file in place containing lines in the format of "variable = number" taking into consideration any whitespace around the equal sign.

Example input:

one=1
two=2
three=3
xyz=20

[download]

Increment the value of a specific variable in the file and write it back out.

Ex: where variable is xyz.

one=1
two=2
three=3
xyz=21

[download]

My attempt:

where xyz is the variable whose value is being incremented by 1 and test.data is the file containing data.

perl -p -i.bak -e 's/$1/$a/ if ((/xyz\s*=\s*([0-9]*)\s*/)&&($a=$1+1))'
+ test.data

[download]
-mlm

In reply to Can anyone make this shorter? by mlm

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