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    <p>I suggest to use Scala 2.10 and macros:</p> <pre><code>object MatrixMacro { import language.experimental.macros import scala.reflect.macros.Context import scala.util.Try implicit class MatrixContext(sc: StringContext) { def matrix(): Array[Array[Int]] = macro matrixImpl } def matrixImpl(c: Context)(): c.Expr[Array[Array[Int]]] = { import c.universe.{ Try =&gt; _, _ } val matrix = Try { c.prefix.tree match { case Apply(_, List(Apply(_, List(Literal(Constant(raw: String)))))) =&gt; def toArrayAST(c: List[TermTree]) = Apply(Select(Select(Ident("scala"), newTermName("Array")), newTermName("apply")), c) val matrix = raw split "\n" map (_.trim) filter (_.nonEmpty) map { _ split "," map (_.trim.toInt) } if (matrix.map(_.length).distinct.size != 1) c.abort(c.enclosingPosition, "rows of matrix do not have the same length") val matrixAST = matrix map (_ map (i =&gt; Literal(Constant(i)))) map (i =&gt; toArrayAST(i.toList)) toArrayAST(matrixAST.toList) } } c.Expr(matrix getOrElse c.abort(c.enclosingPosition, "not a matrix of Int")) } } </code></pre> <p>Usage with:</p> <pre><code>scala&gt; import MatrixMacro._ import MatrixMacro._ scala&gt; matrix"1" res86: Array[Array[Int]] = Array(Array(1)) scala&gt; matrix"1,2,3" res87: Array[Array[Int]] = Array(Array(1, 2, 3)) scala&gt; matrix""" | 1, 2, 3 | 4, 5, 6 | 7, 8, 9 | """ res88: Array[Array[Int]] = Array(Array(1, 2, 3), Array(4, 5, 6), Array(7, 8, 9)) scala&gt; matrix""" | 1, 2 | 1 | """ &lt;console&gt;:57: error: rows of matrix do not have the same length matrix""" ^ scala&gt; matrix"a" &lt;console&gt;:57: error: not a matrix of Int matrix"a" ^ </code></pre> <p>I don't think you will get it shorter. ;)</p>
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    1. COIn general, parsing the matrix from an input string is always a possible solution, even without macros. I'm not yet familiar with 2.10 and macros. Did I get it right that, by using macros, the checks on the input string happen at compile time instead of run time?
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    2. CO@bluenote10: Yes, that is correct. Handling it with a normal string would mean that you must wait until execution of the program to see if you typed the matrix correct.
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    3. CO... which makes this a superb solution :) and a very nice example of macros as well.
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