idea : Rule DSL in F#

[jkone27]

F# and fsx files could be used to write a rule DSL using Computation Expressions, adding type safety and conciseness in the rules (without them having to be dynamic maybe) ?

https://docs.microsoft.com/en-us/dotnet/fsharp/language-reference/computation-expressions

instead of json file

[
  {
    "WorkflowName": "Discount",
    "Rules": [
      {
        "RuleName": "GiveDiscount10",
        "SuccessEvent": "10",
        "ErrorMessage": "One or more adjust rules failed.",
        "ErrorType": "Error",
        "RuleExpressionType": "LambdaExpression",
        "Expression": "input1.country == \"india\" AND input1.loyaltyFactor <= 2 AND input1.totalPurchasesToDate >= 5000"
      },
      {
        "RuleName": "GiveDiscount20",
        "SuccessEvent": "20",
        "ErrorMessage": "One or more adjust rules failed.",
        "ErrorType": "Error",
        "RuleExpressionType": "LambdaExpression",
        "Expression": "input1.country == \"india\" AND input1.loyaltyFactor >= 3 AND input1.totalPurchasesToDate >= 10000"
      }
    ]
  }
]

have an .fs or .fsx file

open Rules.DSL
open Rules.Types

workflow { 
      name "discount"
      rules [
          rule {
               name "GiveDiscount10"
               expression <@@ fun (input : Rules.Types.MyRuleType) -> input.country = "india" && input.loyaltyFactor >= 3 && input.totalPurchasesToDate >= 100 @@>
          }
      ]
}

[evelant]

This would be really cool! I'm new to F# so I'm unsure, is there anything preventing this from being implemented outside of the library? https://learn.microsoft.com/en-us/dotnet/fsharp/language-reference/computation-expressions#creating-a-new-type-of-computation-expression