Flee

2025-10-08 09:49:37 +08:00
commit 284e764345
99 changed files with 21742 additions and 0 deletions
--- a/Parsing/ProductionPatternElement.cs
+++ b/Parsing/ProductionPatternElement.cs
@@ -0,0 +1,138 @@
+using System.Text;
+
+namespace Flee.Parsing
+{
+    /**
+      * A production pattern element. This class represents a reference to
+      * either a token or a production. Each element also contains minimum
+      * and maximum occurence counters, controlling the number of
+      * repetitions allowed. A production pattern element is always
+      * contained within a production pattern rule.
+      */
+    internal class ProductionPatternElement
+    {
+        private readonly bool _token;
+        private readonly int _id;
+        private readonly int _min;
+        private readonly int _max;
+        private LookAheadSet _lookAhead;
+
+        public ProductionPatternElement(bool isToken,
+                                        int id,
+                                        int min,
+                                        int max)
+        {
+
+            this._token = isToken;
+            this._id = id;
+            if (min < 0)
+            {
+                min = 0;
+            }
+            this._min = min;
+            if (max <= 0)
+            {
+                max = Int32.MaxValue;
+            }
+            else if (max < min)
+            {
+                max = min;
+            }
+            this._max = max;
+            this._lookAhead = null;
+        }
+
+        public int Id => _id;
+
+        public int GetId()
+        {
+            return Id;
+        }
+
+        public int MinCount => _min;
+
+        public int GetMinCount()
+        {
+            return MinCount;
+        }
+
+        public int MaxCount => _max;
+
+        public int GetMaxCount()
+        {
+            return MaxCount;
+        }
+
+        internal LookAheadSet LookAhead
+        {
+            get
+            {
+                return _lookAhead;
+            }
+            set
+            {
+                _lookAhead = value;
+            }
+        }
+
+        public bool IsToken()
+        {
+            return _token;
+        }
+
+        public bool IsProduction()
+        {
+            return !_token;
+        }
+
+        public bool IsMatch(Token token)
+        {
+            return IsToken() && token != null && token.Id == _id;
+        }
+
+        public override bool Equals(object obj)
+        {
+            if (obj is ProductionPatternElement)
+            {
+                var elem = (ProductionPatternElement)obj;
+                return this._token == elem._token
+                    && this._id == elem._id
+                    && this._min == elem._min
+                    && this._max == elem._max;
+            }
+            else
+            {
+                return false;
+            }
+        }
+
+        public override int GetHashCode()
+        {
+            return this._id * 37;
+        }
+
+        public override string ToString()
+        {
+            StringBuilder buffer = new StringBuilder();
+
+            buffer.Append(_id);
+            if (_token)
+            {
+                buffer.Append("(Token)");
+            }
+            else
+            {
+                buffer.Append("(Production)");
+            }
+            if (_min != 1 || _max != 1)
+            {
+                buffer.Append("{");
+                buffer.Append(_min);
+                buffer.Append(",");
+                buffer.Append(_max);
+                buffer.Append("}");
+            }
+            return buffer.ToString();
+        }
+    }
+}