codingseb/ExpressionEvaluator

[question] Declare methods in scripts

lofcz opened this issue · 6 comments

lofcz commented

Hi, I'm not quite sure if I missed this in the docs, but is something like this possible?

[void] myMethod([int] a) {

}

myMethod(1);

running the above from new EE().ScriptEvaluate(), myMethod is defined inside of script, not on input / context, [] means optional.

It's not directly possible with the standard syntax of a method for now. But it's possible to declare some multiline lambda like function. I know it's not well documented.
But you can write something like :

var myMethod = (a) => 
{
    //Do something with a
};

myMethod(1);

I will add some docs about this.

Also take note that variables declared in a lambda are scoped (only available) in the lambda block.
But for now variables declared in other types of blocks are not scoped to their block.

var x = 1;

var myMethod = () => 
{
    var a = x + 1;
};

myMethod();

// x will be available here but not a.

But

var x = 1;

if(x == 1)
{
    var a = x+1;
}

// both x and a will be available here.

It's in my todo list to scope variables in each blocks to behave more like in C# but in current version (1.4.18.0) it's not done.

lofcz commented

Thanks for the reply, multiline lambda will do for now. For the sake of backwards compatibility it would be nice to have another setting to toggle this.

It's in my todo list to scope variables in each blocks to behave more like in C# but in current version (1.4.18.0) it's not done.

If possible it would be fine to leave this open for now, for other newcomers around, I guess this would be a frequent question.

it would be nice to have another setting to toggle this.

Yes good idea. I will add an option for this.

If possible it would be fine to leave this open for now, for other newcomers around, I guess this would be a frequent question.

Yes I leave this open.

I added a small documentation about using lambda for method simulation here

I always keep this issue open

lofcz commented

Great job, thanks!