F# doesn't have this built-in, but Microsoft released a sample called "Dynamic LINQ". This allows taking strings and parsing them into typed LINQ Expression Trees. From there, you can just compile them into delegates.
If extra overhead isn't much of an issue, you could have the function compiled into a module and then load that module. Not exactly elegant, but I think it should work.
Thanks to both of you for your help. I will try these suggestions out over the next few weeks.
Best wishes
Chris
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Hi,
I am creating an application when the user should be able to input a custom function. For example, consider the function type: (
float -> float
). The user can input:fun x -> x*x
orfun x -> Math.Exp(x)
.Is there any easy way to "parse" such a function? In other words, given the string input, can I convert it to the function type (let us assume for the moment that I know that x is of type float.) For the standard numeric types, one can input a string and convert it to an integer. Is there any similar way to parse or deserialize such a function? Also, given a function say,
fun x -> x*x
, is there an easy way to write it to a string, and then build it back by reading it from a string?I am trying to avoid writing my own custom parser.
Thanks for any help in this matter.
Regards
Chris