struct Foo:
0 [+4] UInt a
some_complex_offset [+some_complex_size] Structure b
it would be useful to be able to get the values of some_complex_offset and some_complex_size, both in Emboss definitions and in C++.
The tricky part of this is that the offset and size of a field are properties of the structure that contains the field, not properties of the field itself, so a function like $offset_of(b) would need some new machinery to ensure that the argument was a physical field and that it was called in a context where it makes sense.
One thought I had was to make implicit virtual fields $offset_of_b and $size_of_b, similar to the existing implicit virtual field $size_in_bytes. (These might be spelled $offset_of b or $offset_of(b) in an .emb. The C++ names would need to be regular C++ identifiers, or there would need to be contortions in the C++ code generator to make something like view.OffsetOf().b() work.)
Given a structure like:
it would be useful to be able to get the values of
some_complex_offsetandsome_complex_size, both in Emboss definitions and in C++.The tricky part of this is that the offset and size of a field are properties of the structure that contains the field, not properties of the field itself, so a function like
$offset_of(b)would need some new machinery to ensure that the argument was a physical field and that it was called in a context where it makes sense.One thought I had was to make implicit virtual fields
$offset_of_band$size_of_b, similar to the existing implicit virtual field$size_in_bytes. (These might be spelled$offset_of bor$offset_of(b)in an.emb. The C++ names would need to be regular C++ identifiers, or there would need to be contortions in the C++ code generator to make something likeview.OffsetOf().b()work.)