dawgfoto/dmd — comment on commit b47089323b128d02b0c2fb297aacda200643aec3
File:  line 0
By dawgfoto:

The isConst check is plainly inherited from Declaration and only checks the storage class.

We could check only the modifiers of the function type, the storage class
is just a carrier for that information up to FuncDeclaration::semantic
where it is merged into the type modifier, but then this would depend on semantic.