Re: Duplicating behaviour: Similar algorithms and similar data
Rune Allnor <allnor@tele.ntnu.no> wrote:
I am thinking of letting the user interface see only an
object of class JobSpec and use the class ExtendedJobSpec
only inside the computer object where it is needed, as
an internal variable. This provides a certain additional
flexibility I need anyway.
Is it possble to do something like
class JobSpec<template T>{
private
T* p;
}
class ExtendedJobSpec : JobSpec<ExtededParameter>{
// Implement logic specific to ExtendedParametr classes.
};
i.e. the exact type of the template class is specified
as part of the inheritance relation.
Ok then something like
template <class Param> struct job_spec;
template <>
struct job_spec<CoreParam>
{
static void exec(CoreParam *x) {/* handle basic task */}
}
template <>
struct job_spec<ExtendedParam>
{
static void exec(ExtendedParam *p)
{
job_spec<CoreParam>::exec(p);// basic stuff
// extensions here
}
};
template <class T>
inline
void do_job(T *p)
{
job_spec<T>::exec(p);
}
Now the function template param T is determined without promotion or
reduction to a base type. [exact type match chosen] it then calls the
static function in job_spec<T>. Note that the function exec is not
templated so that conversion to a base pointer is considered so no
casting should be needed. Not tested.
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