1erl_features(3)            Erlang Module Definition            erl_features(3)
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NAME

6       erl_features - Feature support.
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DESCRIPTION

9       This  module contains functions for supporting features that can be en‐
10       abled/disabled in Erlang. It should be considered as mostly for  inter‐
11       nal  use,  although  there are some functions that might be useful when
12       writing tools.
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DATA TYPES

15       feature() = atom()
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17       release() = integer() >= 0
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19       status() = experimental | approved | permanent | rejected
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21       type() = extension | backwards_incompatible_change
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EXPORTS

24       all() -> [feature()]
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26              Return a list of all known features. This list will include fea‐
27              tures that have been removed (status rejected) and features that
28              are no longer configurable (status permanent).
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30       configurable() -> [feature()]
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32              Return a list of all configurable features,  that  is,  features
33              with  status  experimental  or  approved. These are the features
34              that can be enabled or disabled.
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36       info(Feature :: feature()) -> FeatureInfoMap | no_return()
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38              Types:
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40                 Description = string()
41                 FeatureInfoMap =
42                     #{description := Description,
43                       short := Description,
44                       type := type(),
45                       keywords := [atom()],
46                       status := status(),
47                       experimental => release(),
48                       approved => release(),
49                       permanent => release(),
50                       rejected => release()}
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52              Return a map containing information about the given feature.
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54       enabled() -> [feature()]
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56              Return a list of the features that are currently  enabled.  Note
57              that  the  set of enabled is set during startup and can then not
58              be changed.
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60       used(Module :: module() | file:filename()) -> [feature()]
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62              Return the list of features enabled when compiling  the  module.
63              The  module need not be loaded, but is found if it exists in the
64              loadpath. If not all features used by the module are enabled  in
65              the runtime, loading the module is not allowed.
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69Ericsson AB                     stdlib 4.3.1.3                 erl_features(3)
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