Adding an optional getname_as_string function

[isaacsas]

One issue with MTK symbol names is the need to use the unicode lower plus in hierarchical systems since a period can't be used, i.e. "act₊vol₁₊x".

Having a getname_as_string function would allow plot recipes, Latexify, and other formatters to have a systematic way to get a nicer representation of the variable/parameter name for display in output (i.e. SciMLBase could then use getname_as_string for plot recipes, and one could get a nicer act.vol₁.x type representation).

[isaacsas]

Maybe get_display_name would be better?

[AayushSabharwal]

So this could be an optional method to implement for symbolic types, which defaults to calling getname on the symbol, converting it to a String and then replacing all ₊ by .?

[isaacsas]

Exactly!

[isaacsas]

So for symbolics it would make that substitution and generate the string, but for normal Symbols it could just call string(sym::Symbol) as it does now.

Maybe the signature is get_display_name(sys, sym) then MTK can just define its own dispatches to do the conversion for MTK systems, while SymbolCaches fallback to normal symbol to string conversion.

[AayushSabharwal]

Why is sys necessary here?

I was thinking something along the lines of

get_display_name(sym::Symbol) = string(sym)

# In Symbolics/SymbolicUtils.jl
get_display_name(sym::Num) = hasname(sym) ? replace(string(getname(sym)), "₊" => ".") : string(Symbol(sym))

[isaacsas]

Adding sys allows anyone who implements the SII interface to add a dispatch and control printing of components of their systems.