m = [
 r->3,
 c->3,
 v->[1,2,3,
     4,5,6,
     7,8,9],

 cell->function(row,col){
   return me.v[me.c*row + col];
 },

 set->function(row,col,val){
   me.v[me.c*row + col] = val;
 }

];

Test.AreEqual(6, m.cell(1,2));

function MatProduct(a,b){
 rez = [
  r->a.r,
  c->b.c,
  v->new double[a.r*b.c],
  cell->a.cell,
  set->a.set
 ];
 
 for(i=0; i<a.r; i++){
   for (j=0; j<b.c; j++){
    s = 0;
    for (v=0; v<a.c; v++){
      s+= a.cell(i,v)*b.cell(v,j);
    } 

    rez.set(i,j,s);
   }
 }

 return rez;
}

r = MatProduct(m,m);
Test.AreEqual(30d, r.cell(0,0));