How to import spaCy’s types avoiding the loading delay?

[danmysak]

Hi,

Let’s say I’m using spaCy conditionally. Let’s also say I want to decrease my script’s loading time by importing the library only when it is actually required. All is good so far: I can simply put import spacy into a function that gets called when the library is needed. But if the function returns a result of type, say, spacy.language.Doc, how do I annotate it without loading the module first? Both import spacy and import spacy.language take a couple of seconds to execute.

Thanks to all the maintainers for the great tool, by the way!

[adrianeboyd]

With the caveat that I'm not an expert on this, I think you can use an if typing.TYPE_CHECKING block to only import if needed for type checking, and then annotate the types as strings. We only do this to avoid circular imports, but I think it would be the same to avoid loading if not needed.

[danmysak]

Thanks!

I never used TYPE_CHECKING before. It seems to do the job, and in my case there was actually no need to change any types to strings—although the code looks somewhat quirky:

if TYPE_CHECKING:
    from spacy.language import Doc, Language
    from spacy.tokens import Token
else:
    Doc = Language = Token = NoReturn

[danmysak]

It’s a real pity though that the same approach cannot be used for spacy.symbols.