implicit conversion PhpArray -> ReadOnlySpan<PhpValue>

Author: jakubmisek

src/Peachpie.CodeAnalysis/Semantics/Conversions.cs

@@ -368,6 +368,9 @@ string[] ImplicitConversionOpNames(TypeSymbol target)
                     // ReadOnlySpan<char> == string.AsSpan()
                     if (target.IsReadOnlySpan(_compilation.GetSpecialType(SpecialType.System_Char))) return new[] { WellKnownMemberNames.ImplicitConversionName, "ToString" };
 
+                    // ReadOnlySpan<PhpValue>
+                    if (target.IsReadOnlySpan(_compilation.CoreTypes.PhpValue.Symbol)) return new[] { WellKnownMemberNames.ImplicitConversionName, "AsSpan", "GetSpan" };
+
                     // AsResource
                     // AsObject
                     // AsPhpValue

src/Peachpie.Runtime/Conversions.cs

@@ -445,6 +445,12 @@ public static bool IsInstanceOf(object obj, PhpTypeInfo tinfo)
 
         #endregion
 
+        #region ToSpan
+
+        public static ReadOnlySpan<PhpValue> ToSpan(PhpArray array) => array.GetSpan();
+
+        #endregion
+
         #region ToDictionary
 
         public static Dictionary<K, V>/*!*/ToDictionary<K, V>(this PhpValue value)

src/Peachpie.Runtime/Dynamic/ConvertExpression.cs

@@ -157,6 +157,13 @@ public static Expression Bind(Expression arg, Type target, Expression ctx)
                 {
                     return BindToDateTime(arg, ctx);
                 }
+
+                // ReadOnlySpan<char>
+                if (target == typeof(ReadOnlySpan<char>))
+                {
+                    // (ReadOnlySpan<char>)ToPhpString() // implicit operator
+                    return Expression.Convert(BindToPhpString(arg, ctx), target);
+                }
             }
 
             // Template: PhpValueConverter.Cast<T>( PhpValue ) : T

src/Peachpie.Runtime/PhpHashtable.cs

@@ -4,6 +4,7 @@
 using System.Diagnostics;
 using System.Linq;
 using System.Runtime.CompilerServices;
+using System.Runtime.InteropServices;
 using System.Text;
 using System.Threading.Tasks;
 using Pchp.Core.Utilities;
@@ -927,6 +928,29 @@ public void AddTo(PhpHashtable/*!*/dst, bool deepCopy)
         /// </summary>
         public PhpValue[] GetValues() => table.GetValues();
 
+        /// <summary>
+        /// Copies values to a new array and get it as a span.
+        /// </summary>
+        public ReadOnlySpan<PhpValue> GetSpan()
+        {
+            if (table.Count == 0)
+            {
+                return default;
+            }
+
+            if (table.Count == 1)
+            {
+                var e = table.GetEnumerator();
+                if (e.MoveNext()) // always true
+                {
+                    return MemoryMarshal.CreateReadOnlySpan(ref e.CurrentValue, 1);
+                }
+            }
+
+            // copy array and get span
+            return GetValues().AsSpan();
+        }
+
         #endregion
 
         #region Misc methods: Sort, Diff, Reverse, Shuffle, Unite