52 lines
901 B
Plaintext
52 lines
901 B
Plaintext
== Why is this an issue?
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Because the ``++is++`` operator performs a cast if the object is not null, using ``++is++`` to check type and then casting the same argument to that type, necessarily performs two casts. The same result can be achieved more efficiently with a single cast using ``++as++``, followed by a null-check.
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=== Noncompliant code example
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[source,csharp]
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----
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if (x is Fruit) // Noncompliant
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{
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var f = (Fruit)x; // or x as Fruit
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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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// C# 6
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var f = x as Fruit;
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if (f != null)
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{
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// ...
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}
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// C# 7
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if (x is Fruit fruit)
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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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include::highlighting.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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