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| -rw-r--r-- | doc/go_spec.html | 26 |
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diff --git a/doc/go_spec.html b/doc/go_spec.html index 4d8312a917..c0ed27730f 100644 --- a/doc/go_spec.html +++ b/doc/go_spec.html @@ -6254,6 +6254,32 @@ if v == nil { </pre> <p> +A <a href="#Type_parameters">type parameter</a> or a <a href="#Type_declarations">parameterized type</a> +may be used as a type in a case. If upon <a href="#Instantiations">instantiation</a> that type turns +out to duplicate another entry in the switch, the first matching case is chosen. +</p> + +<pre> +func f[P any](x any) int { + switch x.(type) { + case P: + return 0 + case string: + return 1 + case []P: + return 2 + case []byte: + return 3 + default: + return 4 + } +} + +var v1 = f[string]("foo") // v1 == 0 +var v2 = f[byte]([]byte{}) // v2 == 2 +</pre> + +<p> The type switch guard may be preceded by a simple statement, which executes before the guard is evaluated. </p> |