import statement placement

[Biotronic via Digitalmars-d-learn]

On Wednesday, 7 June 2017 at 12:39:07 UTC, Russel Winder wrote:
> Are there any idiom rules as to where to put import statements 
> in D?
>
> In Python they can go anywhere but PEP-8 suggests they should 
> all go at the top of a file, just after the module 
> documentation string.

I don't know if there is any official dogma on how to use 
imports, but given that local imports inside templates are only 
loaded if the template is instantiated, there are benefits to 
using local imports in those cases.

Another use for local imports is in unittests - any import that 
is only used in unittests may benefit from being moved from 
module scope to inside the unittests themselves, or for an import 
used by many tests, a version (unittest) block.

In my own code, I use very loose guidelines but prefer to put any 
imports that are used only in one or two functions, inside those 
functions. Imports that are used by multiple functions are placed 
at the top of the file, just below the module declaration (if 
any).

Similarly, I try to use selective imports when only a few symbols 
from a module are used in my module, but find that this becomes 
unwieldy past 3-5 symbols.

--
   Biotronic