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copied!<p>In case classes constructor arguments are vals, so just call:</p> <pre><code>a.input b.input </code></pre> <p>You can also use extractor with the help of <code>unapply</code> method:</p> <pre><code>val Foo(val1) = a val Bar(val2) = b </code></pre> <p>and then use <code>val1</code> and <code>val2</code></p> <p><strong>Update</strong></p> <p>Then you should use pattern matching on your value:</p> <pre><code>value match { case Foo(val1) => val1 case Bar(val1) => val1 } </code></pre> <p>It works just like <code>val Foo(val1) = a</code>, with using generated <code>unapply</code> method (extractor) in your class, and it is also an expression, so you van assign the result to the variable</p> <p>If you have multiple arguments just change PatMat construct according to the number of your parameters, in your case:</p> <pre><code>someMethod(a: Something, b: Something) = (a, b) match { case (Foo(v1), Foo(v2)) => (v1, v2) // or any other logic with values case (Foo(v1), Bar(v2)) => // logic for this case ... // logic for other cases } </code></pre> <p>The more parameters the more cases you should provide, but you case blank cases if you don't need them</p> <pre><code>someMethod(a: Something, b: Something) = (a, b) match { case (Foo(v1), Foo(v2)) => (v1, v2) // or any other logic with values case _ => } </code></pre> <p>in this case all other cases will be ignored, not the best choice, cause the result type will be incorrect. And you also can black values</p> <pre><code>someMethod(a: Something, b: Something) = (a, b) match { case (Foo(v1), _) => v1 // in such case you can work only with v1 ... // logic for other cases } </code></pre>

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