Scala: How to make requirements of the type parametres of generic classes? -

i'm creating parameterized classes c[t] , want make requirements of characteristics of type t able parameter of class. simple if wanted t inherited traits or classes (as ordering). want implement functions well.

for example, i've seen many pre-defined types implement minvalue , maxvalue, type t implement these too. i've received advice define implicit function. wouldn't users obliged implement function these when implemented. implement them @ code too, seems poor quick fix.

for example, when defining heaps, allowd users construct empty heap. in these cases want inicialize value minimum value type t have. code not works.

class heap[t](val value:t,val heaps:list[heap[t]]){     def this()=this(t.minvalue,list()) } 

i love receive advice online scala 2.8 references.

a bunch of things, loosely related virtue of sharing few methods (though different return types). sure sounds ad-hoc polymorphism me!

roll on type class...

class hasminmax[t] {   def maxvalue: t   def minvalue: t }  implicit object inthasminmax extends hasminmax[int] {   def maxvalue = int.maxvalue   def minvalue = int.minvalue }  implicit object doublehasminmax extends hasminmax[double] {   def maxvalue = double.maxvalue   def minvalue = double.minvalue }  // etc  class c[t : hasminmax](param : t) {   val bounds = implicitly[hasminmax[t]]   // use bounds.minvalue or bounds.minvalue required } 

update

the [t : hasminmax] notation context bound, , syntactic sugar for:

class c[t](param : t)(implicit bounds: hasminmax[t]) {   // use bounds.minvalue or bounds.minvalue required }