Subarray not in array module anymore?

Iceypee · June 6, 2023, 4:47am

Is there a reason why subarray isnt in the array base module anymore? And does anyone have a good method of how that was implemented? I have a method but idk it seems to eat lots of cycles.

matthewhammer · June 6, 2023, 2:24pm

Seems to still be there?

github.com

dfinity/motoko-base/blob/3627b49f754bca8444da12c1e12e7c7d534efdd5/src/Array.mo#L728


      
            /// Returns a new subarray from the given array provided the start index and length of elements in the subarray
            ///
            /// Limitations: Traps if the start index + length is greater than the size of the array
            ///
            /// ```motoko include=import
            ///
            /// let array = [1,2,3,4,5];
            /// let subArray = Array.subArray<Nat>(array, 2, 3);
            /// Runtime: O(length);
            /// Space: O(length);
            public func subArray<X>(arr: [X], start: Nat, length: Nat): [X] {
              if (start + length > arr.size()) { Prim.trap("Array.subArray") };
              tabulate<X>(length, func(i) {
                arr[start + i]
              });
            };
          };

Iceypee · June 6, 2023, 7:06pm

Heres the error

Heres the code

I’m using dfx 13.1. Is it just mine?

I did something in my package-set. Could this be causing it?

Iceypee · June 6, 2023, 8:00pm

Well I’ll leave this open as its not fully solved in terms of still being missing from my array module but thanks you helped me figured out my issue internally, I was able to just copy the prim code instead from the github code.

rvanasa · June 6, 2023, 11:02pm

It looks like Array.subArray was added in 0.8.4, so it should be possible to fix this by switching to a more recent base library version in your package-set. If you’re using dfx 0.14.1, the corresponding version tag is moc-0.8.8.

Hope this helps!

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Subarray not in array module anymore?

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