Base for 4.3 work. Split Nadeko.Common into a separate project

src/Nadeko.Common/Extensions/ArrayExtensions.cs

@@ -0,0 +1,51 @@
+namespace Nadeko.Common;
+
+// made for expressions because they almost never get added
+// and they get looped through constantly
+public static class ArrayExtensions
+{
+    /// <summary>
+    ///     Create a new array from the old array + new element at the end
+    /// </summary>
+    /// <param name="input">Input array</param>
+    /// <param name="added">Item to add to the end of the output array</param>
+    /// <typeparam name="T">Type of the array</typeparam>
+    /// <returns>A new array with the new element at the end</returns>
+    public static T[] With<T>(this T[] input, T added)
+    {
+        var newExprs = new T[input.Length + 1];
+        Array.Copy(input, 0, newExprs, 0, input.Length);
+        newExprs[input.Length] = added;
+        return newExprs;
+    }
+
+    /// <summary>
+    ///     Creates a new array by applying the specified function to every element in the input array
+    /// </summary>
+    /// <param name="arr">Array to modify</param>
+    /// <param name="f">Function to apply</param>
+    /// <typeparam name="TIn">Orignal type of the elements in the array</typeparam>
+    /// <typeparam name="TOut">Output type of the elements of the array</typeparam>
+    /// <returns>New array with updated elements</returns>
+    public static TOut[] Map<TIn, TOut>(this TIn[] arr, Func<TIn, TOut> f)
+        => Array.ConvertAll(arr, x => f(x));
+
+    /// <summary>
+    ///     Creates a new array by applying the specified function to every element in the input array
+    /// </summary>
+    /// <param name="col">Array to modify</param>
+    /// <param name="f">Function to apply</param>
+    /// <typeparam name="TIn">Orignal type of the elements in the array</typeparam>
+    /// <typeparam name="TOut">Output type of the elements of the array</typeparam>
+    /// <returns>New array with updated elements</returns>
+    public static TOut[] Map<TIn, TOut>(this IReadOnlyCollection<TIn> col, Func<TIn, TOut> f)
+    {
+        var toReturn = new TOut[col.Count];
+        
+        var i = 0;
+        foreach (var item in col)
+            toReturn[i++] = f(item);
+
+        return toReturn;
+    }
+}