Re: vars in use and require

The use is evaluated at compile time; try eval STRING instead of eval BLOCK:

BEGIN {
  # ...
  eval q{use $v};
  die $@ if $@;
}
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Re^2: vars in use and require by haukex (Archbishop) on Sep 21, 2019 at 23:50 UTC
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.` [download] 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?)	[reply] [d/l] [select]

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Re^2: vars in use and require
by haukex (Archbishop) on Sep 21, 2019 at 23:50 UTC

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?)

[reply]
[d/l]
[select]