Flee

ExpressionElements/Literals/Integral/Int32.cs

@@ -0,0 +1,84 @@
+using System.Globalization;
+using Flee.ExpressionElements.Base.Literals;
+
+using Flee.InternalTypes;
+
+
+namespace Flee.ExpressionElements.Literals.Integral
+{
+    internal class Int32LiteralElement : IntegralLiteralElement
+    {
+        private Int32 _myValue;
+        private const string MinValue = "2147483648";
+        private readonly bool _myIsMinValue;
+        public Int32LiteralElement(Int32 value)
+        {
+            _myValue = value;
+        }
+
+        private Int32LiteralElement()
+        {
+            _myIsMinValue = true;
+        }
+
+        public static Int32LiteralElement TryCreate(string image, bool isHex, bool negated)
+        {
+            if (negated == true & image == MinValue)
+            {
+                return new Int32LiteralElement();
+            }
+            else if (isHex == true)
+            {
+                Int32 value = default(Int32);
+
+                // Since Int32.TryParse will succeed for a string like 0xFFFFFFFF we have to do some special handling
+                if (Int32.TryParse(image, NumberStyles.AllowHexSpecifier, null, out value) == false)
+                {
+                    return null;
+                }
+                else if (value >= 0 & value <= Int32.MaxValue)
+                {
+                    return new Int32LiteralElement(value);
+                }
+                else
+                {
+                    return null;
+                }
+            }
+            else
+            {
+                Int32 value = default(Int32);
+
+                if (Int32.TryParse(image,out value) == true)
+                {
+                    return new Int32LiteralElement(value);
+                }
+                else
+                {
+                    return null;
+                }
+            }
+        }
+
+        public void Negate()
+        {
+            if (_myIsMinValue == true)
+            {
+                _myValue = Int32.MinValue;
+            }
+            else
+            {
+                _myValue = -_myValue;
+            }
+        }
+
+        public override void Emit(FleeILGenerator ilg, IServiceProvider services)
+        {
+            EmitLoad(_myValue, ilg);
+        }
+
+        public override System.Type ResultType => typeof(Int32);
+
+        public int Value => _myValue;
+    }
+}