Hi All,

Request your help on the below error

Program

void main()
{
	import std.stdio:writeln;
	import std.algorithm.iteration : splitter;
	
	auto splitter_ptr = &splitter!((a, b) => a.splitter(b).array);
    string str = "TEST1;TEST2;TEST3";
    auto words = splitter_ptr(str, ';');
    foreach (word; words) { writeln(word); }
}

Error: template instance `splitter!((a, b) => a.splitter(b).array)` does not match any template declaration

From,
Vino

On Thursday, 31 August 2023 at 05:16:02 UTC, Vino wrote:

void main()
{
	import std.stdio:writeln;
	import std.algorithm.iteration : splitter;
	
	auto splitter_ptr = &splitter!((a, b) => a.splitter(b).array);
    string str = "TEST1;TEST2;TEST3";
    auto words = splitter_ptr(str, ';');
    foreach (word; words) { writeln(word); }
}

Error: template instance `splitter!((a, b) => a.splitter(b).array)` does not match any template declaration

Why are you trying to take pointers of lots of different things? You should pretty much never need pointers in normal D code.

On Thursday, 31 August 2023 at 05:16:02 UTC, Vino wrote:

void main()
{
	import std.stdio:writeln;
	import std.algorithm.iteration : splitter;
	
	auto splitter_ptr = &splitter!((a, b) => a.splitter(b).array);
    string str = "TEST1;TEST2;TEST3";
    auto words = splitter_ptr(str, ';');
    foreach (word; words) { writeln(word); }
}

Error: template instance `splitter!((a, b) => a.splitter(b).array)` does not match any template declaration

I'm assuming you want to instantiate splitter and take the address of the resulting function, so that splitter_ptr will be a function pointer or a delegate.

You are getting the compile time arguments to splitter utterly wrong. It should take:

• A function that checks equality between an element and a separator.

• a keepSeparators flag.

• type of the range you're passing in, string in this case.

• type of the separator, char or dchar in this case.

You can find this all in the docs. I think you accidentally passed what you wanted to do with splitter as a compile-time parameter to it.

I don't think it's very practical to try instantiating a complex templated function like splitter without calling it. It's just not designed for that. I'd rather define a function that wraps a call to it, like (not tested, may have errors):

auto splitter_ptr = (string str, dchar sep) => str.splitter(sep).array;

Maybe that's what you tried in the first place. You don't need & here, because a lambda (which we use here) is already a function pointer (or a delegate).

On Thursday, 31 August 2023 at 10:46:53 UTC, Dukc wrote:

This is what I expected, thank you very much