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copied!<p>If using a mere <code>List</code> of <code>List</code> (which in itself cannot guarantee that every sub list is of the same size) is not a problem for you, and you are only concerned with easy syntax and avoiding errors at creation-time, scala has many ways to create nice syntax constructs.</p> <p>One such possibility would be a simple helper:</p> <pre><code>object Matrix { def apply[X]( elements: Tuple3[X, X, X]* ): List[List[X]] = { elements.toList.map(_.productIterator.toList.asInstanceOf[List[X]] ) } // Here you might add other overloads for Tuple4, Tuple5 etc if you need "matrixes" of those sizes } val x = Matrix( (3, 5, 7), (0, 4, 9), (1, 8, 6) ) </code></pre> <p>About your concerns:</p> <blockquote> <p>It repeats "List" over and over again (like there could be anything else besides List)</p> </blockquote> <p>Not the case here.</p> <blockquote> <p>It requires to omit trailing , in every List invocation</p> </blockquote> <p>Unfortunately that is still true here, not much you can do given scala's syntactic rules.</p> <blockquote> <p>If I screw up and insert something besides List() in the middle of array, it will go okay with compiler, but type of x would silently become List[Any] instead of List[List[Int]]:</p> </blockquote> <pre><code>val x = List( List(3, 5, 7), List(0, 4), 9, // <= OK with compiler, silently ruins x List(1, 8, 6) ) </code></pre> <p>The equivalent code now faile to compile:</p> <pre><code>scala> val x = Matrix( | (3, 5, 7), | (0, 4), 9, | (1, 8, 6) | ) <console>:10: error: type mismatch; found : (Int, Int) required: (?, ?, ?) (0, 4), 9, </code></pre> <p>And finally if you want to explicitly specify the type of elements (say that you want to protect against the possibility of inadvertently mixing <code>Int</code>s and <code>Double</code>s), you only have to specify <code>Matrix[Int]</code> instead of the ugly <code>List[List[Int]]</code>:</p> <pre><code>val x = Matrix[Int]( (3, 5, 7), (0, 4, 9), (1, 8, 6) ) </code></pre> <p>EDIT: I see that you replaced <code>List</code> with <code>Array</code> in your question. To use arrays all you have to use is to replace <code>List</code> with <code>Array</code> and <code>toList</code> with <code>toArray</code> in my code above.</p>

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