61 lines
1.2 KiB
Plaintext
61 lines
1.2 KiB
Plaintext
When constraints have not been applied to restrict a generic type parameter to be a reference type, then a value type, such as a ``++struct++``, could also be passed. In such cases, comparing the type parameter to ``++null++`` would always be false, because a ``++struct++`` can be empty, but never ``++null++``. If a value type is truly what's expected, then the comparison should use ``++default()++``. If it's not, then constraints should be added so that no value type can be passed.
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== Noncompliant Code Example
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[source,csharp]
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----
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private bool IsDefault<T>(T value)
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{
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if (value == null) // Noncompliant
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{
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// ...
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}
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// ...
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}
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----
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== Compliant Solution
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[source,csharp]
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----
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private bool IsDefault<T>(T value)
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{
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if(object.Equals(value, default(T)))
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{
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// ...
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}
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// ...
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}
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----
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or
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[source,csharp]
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----
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private bool IsDefault<T>(T value) where T : class
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{
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if (value == null)
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{
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// ...
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}
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// ...
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}
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----
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ifdef::env-github,rspecator-view[]
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'''
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== Implementation Specification
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(visible only on this page)
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include::message.adoc[]
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'''
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== Comments And Links
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(visible only on this page)
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include::comments-and-links.adoc[]
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endif::env-github,rspecator-view[]
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