Implement ForeachStatement for (static) Arrays

I am currently stuck at the semantic analysis.
because depending on the type of the expression that is itterated foreach does diffrent things
how I check If the itterated type has thoose methods ?
-  `popFront()`/`front()`
-  `opApply`

idx is the index variable for the for loop.
So it is the initializer-statement.
If I omit this my foreach test does not compile.