The other case I could think of for static method inheritance is for extending existing behavior, rather than simply overriding it. I've already used this in my own code to great effect. Here's the example:
In the framework I'm working on, I have resource values. Various modules use certain resource values. Think of them a little like the input values that Empty4 provide, but much more comprehensive with categories, etc. I wanted to be able to validate these resources when the EA first runs to make sure it has what it needs (rather than waiting until it tries to open a trade or something and finding out it doesn't have what it needs). Using standard mql you would do something like this:
Code: Select all int init()
{
<validate resources for module 1>
<validate resources for module 2>
.
.
.
<validate resources for module N>
<do whatever else you need to do>
}
Code: Select all int init()
{
bool success;
Resource:Validate(success);
if( !success )
{ Err:Msg("init", "Invalid resource found"); return(0); }
<do whatever else needs to be done>
}
Code: Select all class Resource
{
static extend void Validate(bool& success)
{
success = true;
}
}
Code: Select all class MyModule
{
static void Validate(bool& success) : Resource
{
if( !success ) return;
<do your resource validation - set success to false if fails>
}
}
The net effect is that you've done no hacking whatsoever in any other module other than the module you are directly working in, and everything just magically works.
Let me know if further clarification is needed. |
just an easy way to remember it). And to do this with little or no additional coding to the rest of the library.