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Comment by rajeev-k | Hacker News Reader

I needed the ability to safely execute formulas in my .NET app. My solution was to write a parser and interpreter. Here it is: https://github.com/Rajeev-K/formula-parser

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You can do this already with DataTables, which is basically an in-memory Excel spreadsheet. Bonus is that it also supports Excel functions, and it’s completely safe/sandboxed code.

e.g. https://docs.microsoft.com/en-us/dotnet/api/system.data.data...

I've used FLEE for this. Compiles down to IL so it's fast, you can define your own functions, etc.

https://github.com/mparlak/Flee/wiki/Getting-Started

Do you have examples of the types of "formulas" that you wanted to execute?

Also, how would one execute said formula?

Any valid Visual Basic.NET expression is supported. Here are some examples:

  (latestquote - previousquote) / previousquote
  iif(isonlineorder, "Online", "Retail")
  FirstName & " " & LastName
  iif(IsNothing(Amount), "Amount missing",  Format(Amount, "c2"))
  "Q" & ((OrderDate.Month - 1) \ 3 + 1)
  MonthName(DatePart(DateInterval.Month, Today), false)
  DateAdd(DateInterval.Day, 1, Today)

See this file for example of usage: https://github.com/Rajeev-K/formula-parser/blob/master/src/R...

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