Null object: Difference between revisions
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m ([Erlang] Fix atom list.) |
m ([Erlang] Format code clearly.) |
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Example alternatives: |
Example alternatives: |
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# Something like {ok, 3} or {err, no_more} on error. |
# Something like <pre>{ok, 3}</pre> or <pre>{err, no_more}</pre> on error. |
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# Don't ever allow an undefined return value, and throw an exception instead. |
# Don't ever allow an undefined return value, and throw an exception instead. |
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# Return an atom: |
# Return an atom: |
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## undefined* |
## <pre>undefined</pre>* |
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## undef |
## <pre>undef</pre> |
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## null |
## <pre>null</pre> |
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## nil |
## <pre>nil</pre> |
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## none |
## <pre>none</pre> |
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<pre>undefined</pre> is often used by records as an initial value and the stdlib module. |
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Atoms are erlang's user-defined constants that always evaluates to is itself. It is also equal to no other value else but itself. |
Atoms are erlang's user-defined constants that always evaluates to is itself. It is also equal to no other value else but itself. |
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