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The TypeScript compiler automatically casts a variable to the relevant type inside conditionals where it is possible to infer the type (because ``++typeof++``, ``++instanceof++``, etc was used). This compiler feature makes casts and not-``++null++`` assertions unnecessary.
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== Noncompliant Code Example
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[source,javascript]
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----
function getName(x?: string | UserName) {
if (x) {
console.log("Getting name for " + x!); // Noncompliant
if (typeof x === "string")
return (x as string); // Noncompliant
else
return (x as UserName).name; // Noncompliant
}
return "NoName";
}
----
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== Compliant Solution
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[source,javascript]
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----
function getName(x?: string | UserName) {
if (x) {
console.log("Getting name for " + x);
if (typeof x === "string")
return x;
else
return x.name;
}
return "NoName";
}
----
ifdef::env-github,rspecator-view[]
'''
== Implementation Specification
(visible only on this page)
include::message.adoc[]
include::highlighting.adoc[]
'''
== Comments And Links
(visible only on this page)
include::comments-and-links.adoc[]
endif::env-github,rspecator-view[]