I need a way to use the function body defined in a string (got from the user input)

Of course, the body is regular Kotlin code that can use the 3 variables file, rank and playerHasWhite.

In fact, I need a kind of meta-programming

I mean, given the following snippet :

How can instantiate the function inside myFunction ?

Oh.. I thought you need only to call existing function.

it sounds like you want an

eval

-like function

which has its own myriad of issues

I don’t think Kotlin provides one to evaluate kotlin code in strings

rather than sending whole Kotlin function definitions over the wire, maybe you could instead send a data structure that you can unpack and use to make your function on this end

Thanks 🙂

to make your function

Huh?

So, for the simple example I gave above, how could I do ?

@nil2l or a class, or something else you can parameterize

@loloof64 that really depends on the context this is being used in. You’ll need to identify what parts of the function are consistent through each evaluation and which parts change

But “make function” is what @loloof64 asked initially.. Maybe you mean “call”?

Well, I mean, you could assemble a lambda that uses values that were sent from elsewhere

rather than literally interpret the closure syntax

How does the user input their “function”? if you’re trying to make a command line game, none of the proposed solutions will work…

There’s a lot of context we’re missing here, and I can only suggest so much without it

In fact, it is a complex idea : I want users to be able to set up simple kotlin scripts like

@loloof64 uploaded a file: Untitled

file, rank are variables that they can use right now, but yet has no value, as the function will be called later

You could write your own parser and generate rules, I guess but that could be a tedious work

Yes, I am using Antlr4, but even with it, that's the fact that variables such file and rank are not yet defined, that is getting me into trouble

I've also thought about using a Map for Int variables when parsing, and another one for Boolean ones

But I just looked about a string template if it could save me this hard work

The big challenge is to do some kind of meta-programming in Kotlin : I've not found a way to do this yet

I've been looking everywhere and I can't seem to get that snippet of code here: http://kotlinlang.org/docs/reference/whatsnew11.html#javaxscript-support so that I can use the kotlin script engine but when I do it with the kotlin script utils added to my project and I iterate through all available engines, it doesn't show up, just the js nashorn and the apple script engines. I've been looking all over the place and can't seem to find anywhere on how to use the kotlin script engine so I can embed it into my program. I am looking through the kotlin script engine and I feel like something is missing or wrong. I don't know if this is what I should be including.