get_units() fail on expressions with binomial (causes a crash in Catalyst)

[TorkelE]

Ran into this one while trying to update Catalyst for MTKv9:

@parameters p
ModelingToolkit.get_unit(p) # OK
ModelingToolkit.get_unit(binomial(p,2)) # Error

gives

ERROR: MethodError: no method matching binomial(::DynamicQuantities.Quantity{…}, ::DynamicQuantities.Quantity{…})

Closest candidates are:
  binomial(::Number, ::Integer)
   @ Base intfuncs.jl:1193

Stacktrace:
 [1] get_unit(op::Function, args::Vector{Any})
   @ ModelingToolkit ~/.julia/packages/ModelingToolkit/Mxj1Q/src/systems/unit_check.jl:82
 [2] get_unit(x::SymbolicUtils.BasicSymbolic{Int64})
   @ ModelingToolkit ~/.julia/packages/ModelingToolkit/Mxj1Q/src/systems/unit_check.jl:159
 [3] get_unit(x::Num)
   @ ModelingToolkit ~/.julia/packages/ModelingToolkit/Mxj1Q/src/systems/unit_check.jl:74
 [4] top-level scope
   @ ~/Desktop/Julia Playground/Environment - Catalyst test/playground.jl:96
Some type information was truncated. Use `show(err)` to see complete types.

(Specifying that @parameters p::Int64 does not seem to change this)

[TorkelE]

The same issue goes for factorial

ModelingToolkit.get_unit(factorial(p)) # Error

[ChrisRackauckas]

Isn't this an error for DynamicQuantities missing function?

[TorkelE]

That might def. be the case.

[TorkelE]

solved by SymbolicML/DynamicQuantities.jl#125