what does data in $struct->{data} stands for?

$struct is a hash reference. data is an autovivified key in the referenced hash. (Update: The  -> arrow operator is needed because  $struct is a reference.) Each new hash reference built from each line of input read from an input file or from the  __DATA__ handle (as in the example code) is push-ed to the value of this key.

Also Is it possible to use without pretty?

Did you try it? What happened? (Update: And what does the documentation say?)

Give a man a fish:  <%-{-{-{-<

In reply to Re^3: Create JSON file in specific format by AnomalousMonk
in thread Create JSON file in specific format by ovedpo15

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