Indirectly you led me to this extract from Perl 5.10 delta

$^H and %^H

The implementation of the special variables $^H and %^H has changed, to allow implementing lexical pragmas in pure Perl.

And that leads to perlpragma which should allow what I want. Thanks.

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In reply to Re^2: 5.10: Are scoped constants possible? by BrowserUk
in thread 5.10: Are scoped constants possible? by BrowserUk

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