Merge branch 'master' of github.com:SciSharp/LLamaSharp into rinne-dev

LLama/Extensions/IModelParamsExtensions.cs

@@ -6,7 +6,10 @@ using LLama.Native;
 
 namespace LLama.Extensions
 {
-    internal static class IModelParamsExtensions
+    /// <summary>
+    /// Extention methods to the IModelParams interface
+    /// </summary>
+    public static class IModelParamsExtensions
     {
         /// <summary>
         /// Convert the given `IModelParams` into a `LLamaContextParams`
@@ -31,7 +34,7 @@ namespace LLama.Extensions
             result.n_gpu_layers = @params.GpuLayerCount;
             result.seed = @params.Seed;
             result.f16_kv = @params.UseFp16Memory;
-            result.use_mmap = @params.UseMemoryLock;
+            result.use_mmap = @params.UseMemorymap;
             result.use_mlock = @params.UseMemoryLock;
             result.logits_all = @params.Perplexity;
             result.embedding = @params.EmbeddingMode;

LLama/LLamaEmbedder.cs

@@ -55,7 +55,7 @@ namespace LLama
                 text = text.Insert(0, " ");
             }
 
-            var embed_inp_array = Utils.Tokenize(_ctx, text, addBos, Encoding.GetEncoding(encoding)).ToArray();
+            var embed_inp_array = _ctx.Tokenize(text, addBos, Encoding.GetEncoding(encoding));
 
             // TODO(Rinne): deal with log of prompt
 

LLama/LLamaExecutorBase.cs

@@ -68,9 +68,9 @@ namespace LLama
         public LLamaModel Model => _model;
 
         /// <summary>
-        /// Current "mu" value for mirostate sampling
+        /// Current "mu" value for mirostat sampling
         /// </summary>
-        protected float MirostateMu { get; set; } = float.NaN;
+        protected float? MirostatMu { get; set; }
 
         /// <summary>
         /// 
@@ -391,8 +391,8 @@ namespace LLama
             [JsonPropertyName("last_tokens_maximum_count")]
             public int LastTokensCapacity { get; set; }
 
-            [JsonPropertyName("mirostate_mu")]
-            public float MirostateMu { get; set; }
+            [JsonPropertyName("mirostat_mu")]
+            public float? MirostatMu { get; set; }
         }
     }
 }

LLama/LLamaInstructExecutor.cs

@@ -30,8 +30,8 @@ namespace LLama
         public InstructExecutor(LLamaModel model, string instructionPrefix = "\n\n### Instruction:\n\n",
             string instructionSuffix = "\n\n### Response:\n\n") : base(model)
         {
-            _inp_pfx = _model.Tokenize(instructionPrefix, true).ToArray();
-            _inp_sfx = _model.Tokenize(instructionSuffix, false).ToArray();
+            _inp_pfx = _model.Tokenize(instructionPrefix, true);
+            _inp_sfx = _model.Tokenize(instructionSuffix, false);
             _instructionPrefix = instructionPrefix;
         }
 
@@ -53,7 +53,7 @@ namespace LLama
                 SessionFilePath = _pathSession,
                 SessionTokens = _session_tokens,
                 LastTokensCapacity = _last_n_tokens.Capacity,
-                MirostateMu = MirostateMu
+                MirostatMu = MirostatMu
             };
             return state;
         }
@@ -133,7 +133,7 @@ namespace LLama
 
                 _embed_inps.AddRange(_inp_sfx);
 
-                args.RemainedTokens -= line_inp.Count();
+                args.RemainedTokens -= line_inp.Length;
             }
         }
         /// <inheritdoc />
@@ -146,9 +146,7 @@ namespace LLama
                 {
                     string last_output = "";
                     foreach (var id in _last_n_tokens)
-                    {
-                        last_output += Utils.PtrToString(NativeApi.llama_token_to_str(_model.NativeHandle, id), _model.Encoding);
-                    }
+                        last_output += _model.NativeHandle.TokenToString(id, _model.Encoding);
 
                     foreach (var antiprompt in args.Antiprompts)
                     {
@@ -216,12 +214,12 @@ namespace LLama
                 var tokenDataArray = _model.ApplyPenalty(_last_n_tokens, inferenceParams.LogitBias, repeat_last_n,
                     inferenceParams.RepeatPenalty, inferenceParams.FrequencyPenalty, inferenceParams.PresencePenalty, inferenceParams.PenalizeNL);
 
-                var mu = MirostateMu;
+                var mu = MirostatMu;
                 var id = _model.Sample(
                     tokenDataArray, ref mu, inferenceParams.Temperature, inferenceParams.Mirostat, inferenceParams.MirostatTau,
                     inferenceParams.MirostatEta, inferenceParams.TopK, inferenceParams.TopP, inferenceParams.TfsZ, inferenceParams.TypicalP
                 );
-                MirostateMu = mu;
+                MirostatMu = mu;
 
                 _last_n_tokens.Enqueue(id);
 

LLama/LLamaInteractExecutor.cs

@@ -25,7 +25,7 @@ namespace LLama
         /// <param name="model"></param>
         public InteractiveExecutor(LLamaModel model) : base(model)
         {
-            _llama_token_newline = Utils.Tokenize(_model.NativeHandle, "\n", false, _model.Encoding).ToArray();
+            _llama_token_newline = _model.NativeHandle.Tokenize("\n", false, _model.Encoding);
         }
 
         /// <inheritdoc />
@@ -45,7 +45,7 @@ namespace LLama
                 SessionFilePath = _pathSession,
                 SessionTokens = _session_tokens,
                 LastTokensCapacity = _last_n_tokens.Capacity,
-                MirostateMu = MirostateMu
+                MirostatMu = MirostatMu
             };
             return state;
         }
@@ -114,7 +114,7 @@ namespace LLama
                 }
                 var line_inp = _model.Tokenize(text, false);
                 _embed_inps.AddRange(line_inp);
-                args.RemainedTokens -= line_inp.Count();
+                args.RemainedTokens -= line_inp.Length;
             }
         }
 
@@ -133,7 +133,7 @@ namespace LLama
                     string last_output = "";
                     foreach (var id in _last_n_tokens)
                     {
-                        last_output += Utils.PtrToString(NativeApi.llama_token_to_str(_model.NativeHandle, id), _model.Encoding);
+                        last_output += _model.NativeHandle.TokenToString(id, _model.Encoding);
                     }
 
                     foreach (var antiprompt in args.Antiprompts)
@@ -203,12 +203,12 @@ namespace LLama
                 var tokenDataArray = _model.ApplyPenalty(_last_n_tokens, inferenceParams.LogitBias, repeat_last_n,
                     inferenceParams.RepeatPenalty, inferenceParams.FrequencyPenalty, inferenceParams.PresencePenalty, inferenceParams.PenalizeNL);
 
-                var mu = MirostateMu;
+                var mu = MirostatMu;
                 var id = _model.Sample(
                     tokenDataArray, ref mu, inferenceParams.Temperature, inferenceParams.Mirostat, inferenceParams.MirostatTau, 
                     inferenceParams.MirostatEta, inferenceParams.TopK, inferenceParams.TopP, inferenceParams.TfsZ, inferenceParams.TypicalP
                 );
-                MirostateMu = mu;
+                MirostatMu = mu;
 
                 _last_n_tokens.Enqueue(id);
 

LLama/LLamaModel.cs

@@ -78,10 +78,9 @@ namespace LLama
         /// <param name="text"></param>
         /// <param name="addBos">Whether to add a bos to the text.</param>
         /// <returns></returns>
-        public IEnumerable<llama_token> Tokenize(string text, bool addBos = true)
+        public llama_token[] Tokenize(string text, bool addBos = true)
         {
-            // TODO: reconsider whether to convert to array here.
-            return Utils.Tokenize(_ctx, text, addBos, _encoding);
+            return _ctx.Tokenize(text, addBos, _encoding);
         }
 
         /// <summary>
@@ -93,9 +92,7 @@ namespace LLama
         {
             StringBuilder sb = new();
             foreach(var token in tokens)
-            {
-                sb.Append(Utils.PtrToString(NativeApi.llama_token_to_str(_ctx, token), _encoding));
-            }
+                sb.Append(_ctx.TokenToString(token, _encoding));
             return sb.ToString();
         }
 
@@ -245,7 +242,7 @@ namespace LLama
         /// <param name="tfsZ"></param>
         /// <param name="typicalP"></param>
         /// <returns></returns>
-        public llama_token Sample(LLamaTokenDataArray candidates, ref float mirostat_mu, float temperature = 0.8f, MirostatType mirostat = MirostatType.Disable, 
+        public llama_token Sample(LLamaTokenDataArray candidates, ref float? mirostat_mu, float temperature = 0.8f, MirostatType mirostat = MirostatType.Disable, 
                                   float mirostatTau = 5.0f, float mirostatEta = 0.1f, int topK = 40, float topP = 0.95f, float tfsZ = 1.0f, float typicalP = 1.0f)
         {
             llama_token id;
@@ -256,30 +253,31 @@ namespace LLama
             }
             else
             {
-                if (float.IsNaN(mirostat_mu))
-                    mirostat_mu = 2 * mirostatTau;
-
-                if (mirostat == MirostatType.Mirostat)
-                {
-                    const int mirostat_m = 100;
-                    SamplingApi.llama_sample_temperature(_ctx, candidates, temperature);
-                    id = SamplingApi.llama_sample_token_mirostat(_ctx, candidates, mirostatTau, mirostatEta, mirostat_m, ref mirostat_mu);
-                }
-                else if (mirostat == MirostatType.Mirostat2)
+                var mu = mirostat_mu ?? (2 * mirostatTau);
                 {
-                    SamplingApi.llama_sample_temperature(_ctx, candidates, temperature);
-                    id = SamplingApi.llama_sample_token_mirostat_v2(_ctx, candidates, mirostatTau, mirostatEta, ref mirostat_mu);
-                }
-                else
-                {
-                    // Temperature sampling
-                    SamplingApi.llama_sample_top_k(_ctx, candidates, topK, 1);
-                    SamplingApi.llama_sample_tail_free(_ctx, candidates, tfsZ, 1);
-                    SamplingApi.llama_sample_typical(_ctx, candidates, typicalP, 1);
-                    SamplingApi.llama_sample_top_p(_ctx, candidates, topP, 1);
-                    SamplingApi.llama_sample_temperature(_ctx, candidates, temperature);
-                    id = SamplingApi.llama_sample_token(_ctx, candidates);
+                    if (mirostat == MirostatType.Mirostat)
+                    {
+                        const int mirostat_m = 100;
+                        SamplingApi.llama_sample_temperature(_ctx, candidates, temperature);
+                        id = SamplingApi.llama_sample_token_mirostat(_ctx, candidates, mirostatTau, mirostatEta, mirostat_m, ref mu);
+                    }
+                    else if (mirostat == MirostatType.Mirostat2)
+                    {
+                        SamplingApi.llama_sample_temperature(_ctx, candidates, temperature);
+                        id = SamplingApi.llama_sample_token_mirostat_v2(_ctx, candidates, mirostatTau, mirostatEta, ref mu);
+                    }
+                    else
+                    {
+                        // Temperature sampling
+                        SamplingApi.llama_sample_top_k(_ctx, candidates, topK, 1);
+                        SamplingApi.llama_sample_tail_free(_ctx, candidates, tfsZ, 1);
+                        SamplingApi.llama_sample_typical(_ctx, candidates, typicalP, 1);
+                        SamplingApi.llama_sample_top_p(_ctx, candidates, topP, 1);
+                        SamplingApi.llama_sample_temperature(_ctx, candidates, temperature);
+                        id = SamplingApi.llama_sample_token(_ctx, candidates);
+                    }
                 }
+                mirostat_mu = mu;
             }
             return id;
         }
@@ -299,8 +297,8 @@ namespace LLama
             int repeatLastTokensCount = 64, float repeatPenalty = 1.1f, float alphaFrequency = .0f, float alphaPresence = .0f, 
             bool penalizeNL = true)
         {
-            var n_vocab = NativeApi.llama_n_vocab(_ctx);
-            var logits = Utils.GetLogits(_ctx, n_vocab);
+            var n_vocab = _ctx.VocabCount;
+            var logits = _ctx.GetLogits();
 
             // Apply params.logit_bias map
             if(logitBias is not null)
@@ -352,7 +350,7 @@ namespace LLama
                     n_eval = Params.BatchSize;
                 }
 
-                if(Utils.Eval(_ctx, tokens, i, n_eval, pastTokensCount, Params.Threads) != 0)
+                if (!_ctx.Eval(tokens.AsMemory(i, n_eval), pastTokensCount, Params.Threads))
                 {
                     _logger?.Log(nameof(LLamaModel), "Failed to eval.", ILLamaLogger.LogLevel.Error);
                     throw new RuntimeError("Failed to eval.");
@@ -367,9 +365,7 @@ namespace LLama
         internal IEnumerable<string> GenerateResult(IEnumerable<llama_token> ids)
         {
             foreach(var id in ids)
-            {
-                yield return Utils.TokenToString(id, _ctx, _encoding);
-            }
+                yield return _ctx.TokenToString(id, _encoding);
         }
 
         /// <inheritdoc />

LLama/LLamaStatelessExecutor.cs

@@ -31,7 +31,7 @@ namespace LLama
             _model = model;
             
             var tokens = model.Tokenize(" ", true).ToArray();
-            Utils.Eval(_model.NativeHandle, tokens, 0, tokens.Length, 0, _model.Params.Threads);
+            _model.NativeHandle.Eval(tokens.AsMemory(0, tokens.Length), 0, _model.Params.Threads);
             _originalState = model.GetState();
         }
 
@@ -52,12 +52,12 @@ namespace LLama
             List<llama_token> tokens = _model.Tokenize(text, true).ToList();
             int n_prompt_tokens = tokens.Count;
 
-            Utils.Eval(_model.NativeHandle, tokens.ToArray(), 0, n_prompt_tokens, n_past, _model.Params.Threads);
+            _model.NativeHandle.Eval(tokens.ToArray().AsMemory(0, n_prompt_tokens), n_past, _model.Params.Threads);
 
             lastTokens.AddRange(tokens);
             n_past += n_prompt_tokens;
 
-            var mu = float.NaN;
+            var mu = (float?)null;
             int max_tokens = inferenceParams.MaxTokens < 0 ? int.MaxValue : inferenceParams.MaxTokens;
             for(int i = 0; i < max_tokens; i++)
             {
@@ -76,7 +76,7 @@ namespace LLama
 
                 lastTokens.Add(id);
 
-                string response = Utils.TokenToString(id, _model.NativeHandle, _model.Encoding);
+                string response = _model.NativeHandle.TokenToString(id, _model.Encoding);
                 yield return response;
 
                 tokens.Clear();
@@ -87,7 +87,7 @@ namespace LLama
                     string last_output = "";
                     foreach (var token in lastTokens)
                     {
-                        last_output += Utils.PtrToString(NativeApi.llama_token_to_str(_model.NativeHandle, token), _model.Encoding);
+                        last_output += _model.NativeHandle.TokenToString(token, _model.Encoding);
                     }
 
                     bool should_break = false;

LLama/Native/NativeApi.cs

@@ -207,6 +207,17 @@ namespace LLama.Native
         [DllImport(libraryName, CallingConvention = CallingConvention.Cdecl)]
         public static extern int llama_eval(SafeLLamaContextHandle ctx, llama_token[] tokens, int n_tokens, int n_past, int n_threads);
 
+        /// <summary>
+        /// Run the llama inference to obtain the logits and probabilities for the next token.
+        /// tokens + n_tokens is the provided batch of new tokens to process
+        /// n_past is the number of tokens to use from previous eval calls
+        /// </summary>
+        /// <param name="ctx"></param>
+        /// <param name="tokens"></param>
+        /// <param name="n_tokens"></param>
+        /// <param name="n_past"></param>
+        /// <param name="n_threads"></param>
+        /// <returns>Returns 0 on success</returns>
         [DllImport(libraryName, EntryPoint = "llama_eval", CallingConvention = CallingConvention.Cdecl)]
         public static extern int llama_eval_with_pointer(SafeLLamaContextHandle ctx, llama_token* tokens, int n_tokens, int n_past, int n_threads);
 
@@ -218,6 +229,7 @@ namespace LLama.Native
         /// </summary>
         /// <param name="ctx"></param>
         /// <param name="text"></param>
+        /// <param name="encoding"></param>
         /// <param name="tokens"></param>
         /// <param name="n_max_tokens"></param>
         /// <param name="add_bos"></param>
@@ -256,8 +268,8 @@ namespace LLama.Native
         /// <summary>
         /// Token logits obtained from the last call to llama_eval()
         /// The logits for the last token are stored in the last row
-        /// Can be mutated in order to change the probabilities of the next token
-        /// Rows: n_tokens
+        /// Can be mutated in order to change the probabilities of the next token.<br />
+        /// Rows: n_tokens<br />
         /// Cols: n_vocab
         /// </summary>
         /// <param name="ctx"></param>

LLama/Native/SafeLLamaContextHandle.cs

@@ -1,4 +1,6 @@
 using System;
+using System.Buffers;
+using System.Text;
 using LLama.Exceptions;
 
 namespace LLama.Native
@@ -9,11 +11,29 @@ namespace LLama.Native
     public class SafeLLamaContextHandle
         : SafeLLamaHandleBase
     {
+        #region properties and fields
+        /// <summary>
+        /// Total number of tokens in vocabulary of this model
+        /// </summary>
+        public int VocabCount => ThrowIfDisposed().VocabCount;
+
+        /// <summary>
+        /// Total number of tokens in the context
+        /// </summary>
+        public int ContextSize => ThrowIfDisposed().ContextSize;
+
+        /// <summary>
+        /// Dimension of embedding vectors
+        /// </summary>
+        public int EmbeddingCount => ThrowIfDisposed().EmbeddingCount;
+
         /// <summary>
         /// This field guarantees that a reference to the model is held for as long as this handle is held
         /// </summary>
         private SafeLlamaModelHandle? _model;
+        #endregion
 
+        #region construction/destruction
         /// <summary>
         /// Create a new SafeLLamaContextHandle
         /// </summary>
@@ -42,6 +62,16 @@ namespace LLama.Native
             return true;
         }
 
+        private SafeLlamaModelHandle ThrowIfDisposed()
+        {
+            if (IsClosed)
+                throw new ObjectDisposedException("Cannot use this `SafeLLamaContextHandle` - it has been disposed");
+            if (_model == null || _model.IsClosed)
+                throw new ObjectDisposedException("Cannot use this `SafeLLamaContextHandle` - `SafeLlamaModelHandle` has been disposed");
+
+            return _model;
+        }
+
         /// <summary>
         /// Create a new llama_state for the given model
         /// </summary>
@@ -57,5 +87,103 @@ namespace LLama.Native
 
             return new(ctx_ptr, model);
         }
+        #endregion
+
+        /// <summary>
+        /// Convert the given text into tokens
+        /// </summary>
+        /// <param name="text">The text to tokenize</param>
+        /// <param name="add_bos">Whether the "BOS" token should be added</param>
+        /// <param name="encoding">Encoding to use for the text</param>
+        /// <returns></returns>
+        /// <exception cref="RuntimeError"></exception>
+        public int[] Tokenize(string text, bool add_bos, Encoding encoding)
+        {
+            ThrowIfDisposed();
+
+            // Calculate number of bytes in string, this is a pessimistic estimate of token count. It can't
+            // possibly be more than this.
+            var count = encoding.GetByteCount(text) + (add_bos ? 1 : 0);
+
+            // "Rent" an array to write results into (avoiding an allocation of a large array)
+            var temporaryArray = ArrayPool<int>.Shared.Rent(count);
+            try
+            {
+                // Do the actual conversion
+                var n = NativeApi.llama_tokenize(this, text, encoding, temporaryArray, count, add_bos);
+                if (n < 0)
+                {
+                    throw new RuntimeError("Error happened during tokenization. It's possibly caused by wrong encoding. Please try to " +
+                                           "specify the encoding.");
+                }
+
+                // Copy the results from the rented into an array which is exactly the right size
+                var result = new int[n];
+                Array.ConstrainedCopy(temporaryArray, 0, result, 0, n);
+
+                return result;
+            }
+            finally
+            {
+                ArrayPool<int>.Shared.Return(temporaryArray);
+            }
+        }
+
+        /// <summary>
+        /// Token logits obtained from the last call to llama_eval()
+        /// The logits for the last token are stored in the last row
+        /// Can be mutated in order to change the probabilities of the next token.<br />
+        /// Rows: n_tokens<br />
+        /// Cols: n_vocab
+        /// </summary>
+        /// <param name="ctx"></param>
+        /// <returns></returns>
+        public Span<float> GetLogits()
+        {
+            var model = ThrowIfDisposed();
+
+            unsafe
+            {
+                var logits = NativeApi.llama_get_logits(this);
+                return new Span<float>(logits, model.VocabCount);
+            }
+        }
+
+        /// <summary>
+        /// Convert a token into a string
+        /// </summary>
+        /// <param name="token"></param>
+        /// <param name="encoding"></param>
+        /// <returns></returns>
+        public string TokenToString(int token, Encoding encoding)
+        {
+            return ThrowIfDisposed().TokenToString(token, encoding);
+        }
+
+        /// <summary>
+        /// Convert a token into a span of bytes that could be decoded into a string
+        /// </summary>
+        /// <param name="token"></param>
+        /// <returns></returns>
+        public ReadOnlySpan<byte> TokenToSpan(int token)
+        {
+            return ThrowIfDisposed().TokenToSpan(token);
+        }
+
+        /// <summary>
+        /// Run the llama inference to obtain the logits and probabilities for the next token.
+        /// </summary>
+        /// <param name="tokens">The provided batch of new tokens to process</param>
+        /// <param name="n_past">the number of tokens to use from previous eval calls</param>
+        /// <param name="n_threads"></param>
+        /// <returns>Returns true on success</returns>
+        public bool Eval(Memory<int> tokens, int n_past, int n_threads)
+        {
+            using var pin = tokens.Pin();
+            unsafe
+            {
+                return NativeApi.llama_eval_with_pointer(this, (int*)pin.Pointer, tokens.Length, n_past, n_threads) == 0;
+            }
+        }
     }
 }

LLama/Native/SafeLlamaModelHandle.cs

@@ -13,17 +13,17 @@ namespace LLama.Native
         /// <summary>
         /// Total number of tokens in vocabulary of this model
         /// </summary>
-        public int VocabCount { get; set; }
+        public int VocabCount { get; }
 
         /// <summary>
         /// Total number of tokens in the context
         /// </summary>
-        public int ContextSize { get; set; }
+        public int ContextSize { get; }
 
         /// <summary>
         /// Dimension of embedding vectors
         /// </summary>
-        public int EmbeddingCount { get; set; }
+        public int EmbeddingCount { get; }
 
         internal SafeLlamaModelHandle(IntPtr handle)
             : base(handle)

LLama/Utils.cs

@@ -2,10 +2,8 @@
 using LLama.Native;
 using System;
 using System.Collections.Generic;
-using System.Linq;
 using System.Runtime.InteropServices;
 using System.Text;
-using LLama.Exceptions;
 using LLama.Extensions;
 
 namespace LLama
@@ -27,41 +25,36 @@ namespace LLama
             }
         }
 
+        [Obsolete("Use SafeLLamaContextHandle Tokenize method instead")]
         public static IEnumerable<llama_token> Tokenize(SafeLLamaContextHandle ctx, string text, bool add_bos, Encoding encoding)
         {
-            var cnt = encoding.GetByteCount(text);
-            llama_token[] res = new llama_token[cnt + (add_bos ? 1 : 0)];
-            int n = NativeApi.llama_tokenize(ctx, text, encoding, res, res.Length, add_bos);
-            if (n < 0)
-            {
-                throw new RuntimeError("Error happened during tokenization. It's possibly caused by wrong encoding. Please try to " +
-                    "specify the encoding.");
-            }
-            return res.Take(n);
+            return ctx.Tokenize(text, add_bos, encoding);
         }
 
-        public static unsafe Span<float> GetLogits(SafeLLamaContextHandle ctx, int length)
+        [Obsolete("Use SafeLLamaContextHandle GetLogits method instead")]
+        public static Span<float> GetLogits(SafeLLamaContextHandle ctx, int length)
         {
-            var logits = NativeApi.llama_get_logits(ctx);
-            return new Span<float>(logits, length);
+            if (length != ctx.VocabCount)
+                throw new ArgumentException("length must be the VocabSize");
+
+            return ctx.GetLogits();
         }
 
-        public static unsafe int Eval(SafeLLamaContextHandle ctx, llama_token[] tokens, int startIndex, int n_tokens, int n_past, int n_threads)
+        [Obsolete("Use SafeLLamaContextHandle Eval method instead")]
+        public static int Eval(SafeLLamaContextHandle ctx, llama_token[] tokens, int startIndex, int n_tokens, int n_past, int n_threads)
         {
-            int result;
-            fixed(llama_token* p = tokens)
-            {
-                result = NativeApi.llama_eval_with_pointer(ctx, p + startIndex, n_tokens, n_past, n_threads);
-            }
-            return result;
+            var slice = tokens.AsMemory().Slice(startIndex, n_tokens);
+            return ctx.Eval(slice, n_past, n_threads) ? 0 : 1;
         }
 
+        [Obsolete("Use SafeLLamaContextHandle TokenToString method instead")]
         public static string TokenToString(llama_token token, SafeLLamaContextHandle ctx, Encoding encoding)
         {
-            return PtrToString(NativeApi.llama_token_to_str(ctx, token), encoding);
+            return ctx.TokenToString(token, encoding);
         }
 
-        public static unsafe string PtrToString(IntPtr ptr, Encoding encoding)
+        [Obsolete("No longer used internally by LlamaSharp")]
+        public static string PtrToString(IntPtr ptr, Encoding encoding)
         {
 #if NET6_0_OR_GREATER
             if(encoding == Encoding.UTF8)
@@ -77,21 +70,24 @@ namespace LLama
                 return Marshal.PtrToStringAuto(ptr);
             }
 #else
-            byte* tp = (byte*)ptr.ToPointer();
-            List<byte> bytes = new();
-            while (true)
+            unsafe
             {
-                byte c = *tp++;
-                if (c == '\0')
-                {
-                    break;
-                }
-                else
+                byte* tp = (byte*)ptr.ToPointer();
+                List<byte> bytes = new();
+                while (true)
                 {
-                    bytes.Add(c);
+                    byte c = *tp++;
+                    if (c == '\0')
+                    {
+                        break;
+                    }
+                    else
+                    {
+                        bytes.Add(c);
+                    }
                 }
+                return encoding.GetString(bytes.ToArray());
             }
-            return encoding.GetString(bytes.ToArray());
 #endif
         }
     }