Weak deps/Extension pkgs on Unitful?

[anandijain]

julia> @time_imports using SBML
      2.5 ms  Zlib_jll
      3.1 ms  Libiconv_jll
      1.8 ms  XML2_jll
     63.9 ms  SBML_jll
      1.9 ms  DocStringExtensions
     10.9 ms  IfElse
      8.6 ms  ConstructionBase
    832.3 ms  Unitful
    160.4 ms  SBML

I usually don't use the Unitful stuff, so maybe it would be a good candidate for https://pkgdocs.julialang.org/dev/creating-packages/#Weak-dependencies

this is off the cuff, no urgency

[exaexa]

Hi, yeah this is very true and actually one of the reason I had to remove symbolics (the overhead of these was just too much). If there's some straightforward and reliable way to make unitful load on demand, let's do it. We could even push Unitful to a separate package (UnitfulSBML.jl? :D ), but l'd still prefer something that leaves the repo in one piece.

Btw, how does the Julia1.9 precompilation speedup affect unitful? Wouldn't there be some opportunity to massively fix the load times by fixing methods, like as happened with JuMP?