I can't understand how to define default values for functions in my library. Default values tend to be ignored and I get "wrong parameters count" error message.
Here is my example. I created simple test library experts\libraries\test.mq4
:
void test(int i = 0) // Note the default value for "i"
{
}
Then I created .mqh
file as experts\include\test.mqh
:
#import "test.ex4"
void test(int i = 0); // Note the default value for "i"
#import
Now I create simple expert "experts\simpletest.mq4":
#include <test.mqh>
int start()
{
// Should be able to call test() function without providing any arguments,
// because it has default value.
// If I change this line to test(0), everything compiles correctly
test(); // Causes "wrong parameters count" compilation error
return(0);
}
And I get the following error for test() function call:
')' - wrong parameters count
If I change this function call to test(0)
, everything compiles, but I should be able to call test()
function without providing any parameters, because I have default value for first parameter in .mqh file, like this: void test(int i = 0);
Why it doesn't use the default value?
I search google for any clue, but can't find any references about this problem. Anybody knows?
This is not possible as stated in the MQL Documentation:
MQL4-library functions imported within other modules cannot have parameters initialized by default values.