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    <p>If <code>dim</code> returns an ArrayBuffer, then, no, you can't just use <code>println(multiarray.dim)</code>. Here are some simple alternatives though:</p> <ol> <li><p><strong>Define a method to return the dimensions as a String (in your multiarray class):</strong></p> <pre><code>def dimStr = dim mkString "x" </code></pre></li> <li><p><strong>Define a utility method for printing:</strong></p> <pre><code>def printdim(buffer: ArrayBuffer[Int]) = println(buffer mkString "x") // or def printdim(multiarray: MultiArray) = println(multiarray.dim mkString "x") </code></pre></li> </ol> <p><strong>Generalizing toString:</strong></p> <p>With a bit more effort, you can define a version of <code>println</code> that will work the way you'd like. The idea is to abstract the String-creation logic. The power of this approach is that, once the basic infrastructure is in place, you're able to control the "stringification" of any type just by bringing an appropriate implicit into scope.</p> <p>Start by defining a type class:</p> <pre><code>trait Stringable[T] extends (T =&gt; String) </code></pre> <p>Provide a default implementation of the type class (which just falls back on the ordinary <code>toString</code> method):</p> <pre><code>class DefaultStringable[T] extends Stringable[T] { def apply(x: T) = x.toString } object DefaultStringable { implicit def any2stringable[T]: Stringable[T] = new DefaultStringable[T] } </code></pre> <p>Implement the type class for your use case:</p> <pre><code>implicit object DimIsStringable extends Stringable[ArrayBuffer[Int]] { def apply(buf: ArrayBuffer[Int]) = buf mkString "x" } </code></pre> <p>Define a print method that uses the type class:</p> <pre><code>def myprintln[T](x: T)(implicit e: Stringable[T]) = e(x) </code></pre> <p>Fun.</p> <pre><code>import DefaultStringable._ myprintln(ArrayBuffer(1,2,3)) // prints "ArrayBuffer(1, 2, 3)" </code></pre> <p>Profit! </p> <pre><code>import DimIsStringable._ myprintln(ArrayBuffer(1,2,3)) // prints "1x2x3" </code></pre> <p>If desired, you can make the default type class always available without requiring any import. To do so, you provide the conversion in a companion module to the Stringable trait (as demonstrated below). The disadvantage of doing so is that you'll no longer have a compiler error to alert you if you forget to import an appropriate Stringable.</p> <pre><code>object Stringable { implicit def any2stringable[T]: Stringable[T] = new DefaultStringable[T] } </code></pre>
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    1. USAaron Novstrup
    1. USAaron Novstrup
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    1. CO@Aaron Novstrup I really like your approach, as I might need to print other variables specifically. But what if I have also some `ArrayBuffer`s that I want to print as `ArrayBuffer(1,2,3)`? Is it possible to restrict to the `dim` only?
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    2. COOne of the advantages of this approach is that you control how a given type will be converted to a String by importing an appropriate conversion into scope. But once you import an implicit `Stringable[SomeType]`, everything of type `SomeType` has to use that conversion or you must explicitly pass the conversion you want to use: `myprintln(ArrayBuffer(1,2,3))(DefaultStringable)`.
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      1. USAaron Novstrup
    3. COYou could define a Stringable[MultiArray], though. Or have `dim` return a type that contains an `ArrayBuffer`, and define a Stringable for that type.
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