The trick is that perl will evaluate a literal number as hex if you prefix it with '0x', you then need to use eval to force perl to re-evalute it as a number instead of a string.
Any reason not use the build in hex function, and instead use an eval, which, if the data comes from an untrusted source, has potential to have some "unwanted"side effects?

In reply to Re^2: Basic transformations by JavaFan
in thread Basic transformations by Anonymous Monk

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