in reply to Re^2: reading a JSON object
in thread reading a JSON object

The error message indicates you're using the string timestamp in subtraction.

$ perl -wE 'say "timestamp" - 2'
Argument "timestamp" isn't numeric in subtraction (-) at -e line 1.
-2

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I don't see how the string can be meaningfully converted to a number. Please, show the code that demonstrates the problem. Are you using the string directly instead of using it as a hash key?

map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]

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