I was going to suggest something along the lines of BEGIN { eval "use $]; 1" or die $@ } instead (Bug in eval in pre-5.14), but it doesn't actually work to enable features:

$ perl -e 'BEGIN { eval "use $]; 1" or die $@ } say "foo"'
String found where operator expected at -e line 1, near "say "foo""
    (Do you need to predeclare say?)
syntax error at -e line 1, near "say "foo""
Execution of -e aborted due to compilation errors.

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Because the scope of feature is limited to the lexical scope.

So, Anonymous Monk, to echo stevieb: Why do you (think you) need this? (Why try to do something dynamically that is determined statically / at compile time?)

In reply to Re^2: vars in use and require by haukex
in thread vars in use and require by Anonymous Monk

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