[Perl.Pocket.Reference.5th.Edition]04_Features
. Features
As of version 5.10, Perl supports features to selectively enhance the syntax and semantics of the language. Features can be en- abled with use feature and disabled with no feature, see the section Pragmatic Modules on page 17.
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Feature | Perl | Description
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say | 5.10 | Enables the keyword say.
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state | 5.10 | Enables the keyword state.
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switch | 5.10 | Enables the keywords given,
| | when, break, and default.
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unicode_strings | 5.12 | Enables Unicode semantics
| | in all string operations.
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:5.10 | 5.10 | All 5.10 features.
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:5.12 | 5.12 | All 5.10 and 5.12 features.
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:5.14 | 5.14 | All 5.10, 5.12 and 5.14 features.
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Feature bundles like :5.14 provide a quick means to get a fully featured Perl, although it is easier to automatically enable version dependent features with:
use 5.14.0;