use yield return instead of List

joelverhagen · Dec 26, 2021 · cc55d07 · cc55d07
1 parent 20cd041
commit cc55d07
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Showing 29 changed files with 32 additions and 118 deletions.
diff --git a/NCsvPerf/CsvReadable/Implementations/CSVFile.cs b/NCsvPerf/CsvReadable/Implementations/CSVFile.cs
@@ -19,7 +19,6 @@ public CSVFile(ActivationMethod activationMethod)
         public IEnumerable<T> GetRecords<T>(MemoryStream stream) where T : ICsvReadable, new()
         {
             var activate = ActivatorFactory.Create<T>(_activationMethod);
-            var allRecords = new List<T>();
 
             var config = new global::CSVFile.CSVSettings
             {
@@ -32,11 +31,9 @@ public CSVFile(ActivationMethod activationMethod)
                 {
                     var record = activate();
                     record.Read(i => row[i]);
-                    allRecords.Add(record);
+                    yield return record;
                 }
             }
-
-            return allRecords;
         }
     }
 }
diff --git a/NCsvPerf/CsvReadable/Implementations/CommonLibrary_Net.cs b/NCsvPerf/CsvReadable/Implementations/CommonLibrary_Net.cs
@@ -22,7 +22,6 @@ public CommonLibrary_NET(ActivationMethod activationMethod)
         public IEnumerable<T> GetRecords<T>(MemoryStream stream) where T : ICsvReadable, new()
         {
             var activate = ActivatorFactory.Create<T>(_activationMethod);
-            var allRecords = new List<T>();
 
             string text;
             using (var reader = new StreamReader(stream))
@@ -37,11 +36,9 @@ public CommonLibrary_NET(ActivationMethod activationMethod)
                 {
                     var record = activate();
                     record.Read(i => row[i]);
-                    allRecords.Add(record);
+                    yield return record;
                 }
             }
-
-            return allRecords;
         }
     }
 }
diff --git a/NCsvPerf/CsvReadable/Implementations/Csv.cs b/NCsvPerf/CsvReadable/Implementations/Csv.cs
@@ -19,7 +19,6 @@ public Csv(ActivationMethod activationMethod)
         public IEnumerable<T> GetRecords<T>(MemoryStream stream) where T : ICsvReadable, new()
         {
             var activate = ActivatorFactory.Create<T>(_activationMethod);
-            var allRecords = new List<T>();
 
             using (var reader = new StreamReader(stream))
             {
@@ -33,11 +32,9 @@ public Csv(ActivationMethod activationMethod)
                 {
                     var record = activate();
                     record.Read(i => row[i]);
-                    allRecords.Add(record);
+                    yield return record;
                 }
             }
-
-            return allRecords;
         }
     }
 }
diff --git a/NCsvPerf/CsvReadable/Implementations/CsvHelper.cs b/NCsvPerf/CsvReadable/Implementations/CsvHelper.cs
@@ -20,7 +20,6 @@ public CsvHelper(ActivationMethod activationMethod)
         public IEnumerable<T> GetRecords<T>(MemoryStream stream) where T : ICsvReadable, new()
         {
             var activate = ActivatorFactory.Create<T>(_activationMethod);
-            var allRecords = new List<T>();
 
             using (var reader = new StreamReader(stream))
             {
@@ -33,11 +32,9 @@ public CsvHelper(ActivationMethod activationMethod)
                 {
                     var record = activate();
                     record.Read(i => csvParser[i]);
-                    allRecords.Add(record);
+                    yield return record;
                 }
             }
-
-            return allRecords;
         }
     }
 }
diff --git a/NCsvPerf/CsvReadable/Implementations/CsvTextFieldParser.cs b/NCsvPerf/CsvReadable/Implementations/CsvTextFieldParser.cs
@@ -19,7 +19,6 @@ public CsvTextFieldParser(ActivationMethod activationMethod)
         public IEnumerable<T> GetRecords<T>(MemoryStream stream) where T : ICsvReadable, new()
         {
             var activate = ActivatorFactory.Create<T>(_activationMethod);
-            var allRecords = new List<T>();
 
             using (var reader = new StreamReader(stream))
             {
@@ -29,11 +28,9 @@ public CsvTextFieldParser(ActivationMethod activationMethod)
                     var fields = parser.ReadFields();
                     var record = activate();
                     record.Read(i => fields[i]);
-                    allRecords.Add(record);
+                    yield return record;
                 }
             }
-
-            return allRecords;
         }
     }
 }
diff --git a/NCsvPerf/CsvReadable/Implementations/CsvTools.cs b/NCsvPerf/CsvReadable/Implementations/CsvTools.cs
@@ -21,7 +21,6 @@ public CsvTools(ActivationMethod activationMethod)
         public IEnumerable<T> GetRecords<T>(MemoryStream stream) where T : ICsvReadable, new()
         {
             var activate = ActivatorFactory.Create<T>(_activationMethod);
-            var allRecords = new List<T>();
 
             if (stream.Length > 0)
             {
@@ -30,17 +29,15 @@ public CsvTools(ActivationMethod activationMethod)
                 // Read header as a row.
                 var r = activate();
                 r.Read(i => table.ColumnNames.ElementAt(i));
-                allRecords.Add(r);
+                yield return r;
 
                 foreach (var row in table.Rows)
                 {
                     var record = activate();
                     record.Read(i => row.Values[i]);
-                    allRecords.Add(record);
+                    yield return record;
                 }
             }
-
-            return allRecords;
         }
     }
 }
diff --git a/NCsvPerf/CsvReadable/Implementations/Ctl_Data.cs b/NCsvPerf/CsvReadable/Implementations/Ctl_Data.cs
@@ -20,7 +20,6 @@ public Ctl_Data(ActivationMethod activationMethod)
         public IEnumerable<T> GetRecords<T>(MemoryStream stream) where T : ICsvReadable, new()
         {
             var activate = ActivatorFactory.Create<T>(_activationMethod);
-            var allRecords = new List<T>();
 
             using (var streamReader = new StreamReader(stream))
             {
@@ -32,11 +31,9 @@ public Ctl_Data(ActivationMethod activationMethod)
                     // Empty fields are returned as null by this library. Convert that to empty string to be more
                     // consistent with other libraries.
                     record.Read(i => csvReader.CurrentRow[i].Value ?? string.Empty);
-                    allRecords.Add(record);
+                    yield return record;
                 }
             }
-
-            return allRecords;
         }
     }
 }
diff --git a/NCsvPerf/CsvReadable/Implementations/DSV.cs b/NCsvPerf/CsvReadable/Implementations/DSV.cs
@@ -21,7 +21,6 @@ public Dsv(ActivationMethod activationMethod)
         public IEnumerable<T> GetRecords<T>(MemoryStream stream) where T : ICsvReadable, new()
         {
             var activate = ActivatorFactory.Create<T>(_activationMethod);
-            var allRecords = new List<T>();
 
             using (var reader = new StreamReader(stream))
             {
@@ -30,11 +29,9 @@ public Dsv(ActivationMethod activationMethod)
                 {
                     var record = activate();
                     record.Read(i => row[i]);
-                    allRecords.Add(record);
+                    yield return record;
                 }
             }
-
-            return allRecords;
         }
 
         static IEnumerable<string> EnumerateLines(TextReader r)

diff --git a/NCsvPerf/CsvReadable/Implementations/FastCsvParser.cs b/NCsvPerf/CsvReadable/Implementations/FastCsvParser.cs
@@ -24,19 +24,16 @@ public FastCsvParser(ActivationMethod activationMethod)
         public IEnumerable<T> GetRecords<T>(MemoryStream stream) where T : ICsvReadable, new()
         {
             var activate = ActivatorFactory.Create<T>(_activationMethod);
-            var allRecords = new List<T>();
 
             using (var parser = new global::FastCsvParser.CsvReader(stream, Encoding.UTF8))
             {
                 while (parser.MoveNext())
                 {
                     var record = activate();
                     record.Read(i => parser.Current[i]);
-                    allRecords.Add(record);
+                    yield return record;
                 }
             }
-
-            return allRecords;
         }
     }
 }
diff --git a/NCsvPerf/CsvReadable/Implementations/FileHelpers.cs b/NCsvPerf/CsvReadable/Implementations/FileHelpers.cs
@@ -20,7 +20,6 @@ public FileHelpers(ActivationMethod activationMethod)
         public IEnumerable<T> GetRecords<T>(MemoryStream stream) where T : ICsvReadable, new()
         {
             var activate = ActivatorFactory.Create<T>(_activationMethod);
-            var allRecords = new List<T>();
 
             using (var reader = new StreamReader(stream))
             {
@@ -36,12 +35,10 @@ public FileHelpers(ActivationMethod activationMethod)
                         // bind directly to the PackageAsset.
                         var record = activate();
                         record.Read(i => item.GetString(i));
-                        allRecords.Add(record);
+                        yield return record;
                     }
                 }
             }
-
-            return allRecords;
         }
         [global::FileHelpers.DelimitedRecord(",")]
         public class PackageAssetData

diff --git a/NCsvPerf/CsvReadable/Implementations/FlatFiles.cs b/NCsvPerf/CsvReadable/Implementations/FlatFiles.cs
@@ -19,7 +19,6 @@ public FlatFiles(ActivationMethod activationMethod)
         public IEnumerable<T> GetRecords<T>(MemoryStream stream) where T : ICsvReadable, new()
         {
             var activate = ActivatorFactory.Create<T>(_activationMethod);
-            var allRecords = new List<T>();
 
             using (var reader = new StreamReader(stream))
             {
@@ -30,11 +29,9 @@ public FlatFiles(ActivationMethod activationMethod)
                     var values = csvReader.GetValues();
                     var record = activate();
                     record.Read(i => values[i]?.ToString() ?? string.Empty);
-                    allRecords.Add(record);
+                    yield return record;
                 }
             }
-
-            return allRecords;
         }
     }
 }
diff --git a/NCsvPerf/CsvReadable/Implementations/FluentCsv.cs b/NCsvPerf/CsvReadable/Implementations/FluentCsv.cs
@@ -19,7 +19,6 @@ public FluentCSV(ActivationMethod activationMethod)
         public IEnumerable<T> GetRecords<T>(MemoryStream stream) where T : ICsvReadable, new()
         {
             var activate = ActivatorFactory.Create<T>(_activationMethod);
-            var allRecords = new List<T>();
 
             using (var reader = new StreamReader(stream))
             {
@@ -30,11 +29,9 @@ public FluentCSV(ActivationMethod activationMethod)
                     var row = splitter.SplitColumns(line, ",");
                     var record = activate();
                     record.Read(i => row[i]);
-                    allRecords.Add(record);
+                    yield return record;
                 }
             }
-
-            return allRecords;
         }
     }
 }
diff --git a/NCsvPerf/CsvReadable/Implementations/HomeGrown.cs b/NCsvPerf/CsvReadable/Implementations/HomeGrown.cs
@@ -21,7 +21,6 @@ public HomeGrown(ActivationMethod activationMethod)
         public IEnumerable<T> GetRecords<T>(MemoryStream stream) where T : ICsvReadable, new()
         {
             var activate = ActivatorFactory.Create<T>(_activationMethod);
-            var allRecords = new List<T>();
             var fields = new List<string>();
             var builder = new StringBuilder();
 
@@ -31,11 +30,9 @@ public HomeGrown(ActivationMethod activationMethod)
                 {
                     var record = activate();
                     record.Read(i => fields[i]);
-                    allRecords.Add(record);
+                    yield return record;
                 }
             }
-
-            return allRecords;
         }
     }
 }
diff --git a/NCsvPerf/CsvReadable/Implementations/KBCsv.cs b/NCsvPerf/CsvReadable/Implementations/KBCsv.cs
@@ -21,7 +21,6 @@ public KBCsv(ActivationMethod activationMethod)
         public IEnumerable<T> GetRecords<T>(MemoryStream stream) where T : ICsvReadable, new()
         {
             var activate = ActivatorFactory.Create<T>(_activationMethod);
-            var allRecords = new List<T>();
             var stringPool = new StringPool(128);
 
             using (var reader = new StreamReader(stream))
@@ -33,11 +32,9 @@ public KBCsv(ActivationMethod activationMethod)
 
                     var record = activate();
                     record.Read(i => row[i]);
-                    allRecords.Add(record);
+                    yield return record;
                 }
             }
-
-            return allRecords;
         }
     }
 }
diff --git a/NCsvPerf/CsvReadable/Implementations/LinqToCsv.cs b/NCsvPerf/CsvReadable/Implementations/LinqToCsv.cs
@@ -20,7 +20,6 @@ public LinqToCsv(ActivationMethod activationMethod)
         public IEnumerable<T> GetRecords<T>(MemoryStream stream) where T : ICsvReadable, new()
         {
             var activate = ActivatorFactory.Create<T>(_activationMethod);
-            var allRecords = new List<T>();
 
             using (var reader = new StreamReader(stream))
             {
@@ -33,11 +32,9 @@ public LinqToCsv(ActivationMethod activationMethod)
                 {
                     var record = activate();
                     record.Read(i => row[i].Value ?? string.Empty);
-                    allRecords.Add(record);
+                    yield return record;
                 }
             }
-
-            return allRecords;
         }
 
         private class DataRow : List<DataRowItem>, IDataRow

diff --git a/NCsvPerf/CsvReadable/Implementations/LumenWorksCsvReader.cs b/NCsvPerf/CsvReadable/Implementations/LumenWorksCsvReader.cs
@@ -19,7 +19,6 @@ public LumenWorksCsvReader(ActivationMethod activationMethod)
         public IEnumerable<T> GetRecords<T>(MemoryStream stream) where T : ICsvReadable, new()
         {
             var activate = ActivatorFactory.Create<T>(_activationMethod);
-            var allRecords = new List<T>();
 
             using (var reader = new StreamReader(stream))
             using (var csvReader = new LumenWorks.Framework.IO.Csv.CsvReader(reader, hasHeaders: false))
@@ -28,11 +27,9 @@ public LumenWorksCsvReader(ActivationMethod activationMethod)
                 {
                     var record = activate();
                     record.Read(i => csvReader[i]);
-                    allRecords.Add(record);
+                    yield return record;
                 }
             }
-
-            return allRecords;
         }
     }
 }
diff --git a/NCsvPerf/CsvReadable/Implementations/Microsoft_Data_Analsysis.cs b/NCsvPerf/CsvReadable/Implementations/Microsoft_Data_Analsysis.cs
@@ -24,7 +24,6 @@ public Microsoft_Data_Analysis(ActivationMethod activationMethod)
         public IEnumerable<T> GetRecords<T>(MemoryStream stream) where T : ICsvReadable, new()
         {
             var activate = ActivatorFactory.Create<T>(_activationMethod);
-            var allRecords = new List<T>();
 
             // This only works for data with exactly 25 columns.
             // You must either provide the column types, or the types will be
@@ -38,17 +37,15 @@ public Microsoft_Data_Analysis(ActivationMethod activationMethod)
             catch(FormatException e)
             {
                 if (e.Message == "Empty file")
-                    return allRecords;
+                    yield break;
                 throw;
             }
             foreach (var row in frame.Rows)
             {
                 var record = activate();
                 record.Read(i => row[i].ToString());
-                allRecords.Add(record);
+                yield return record;
             }
-
-            return allRecords;
         }
     }
 }
diff --git a/NCsvPerf/CsvReadable/Implementations/Microsoft_ML.cs b/NCsvPerf/CsvReadable/Implementations/Microsoft_ML.cs
@@ -35,7 +35,6 @@ public Microsoft_ML(ActivationMethod activationMethod)
             }
 
             var activate = ActivatorFactory.Create<T>(_activationMethod);
-            var allRecords = new List<T>();
             var mlc = new MLContext();
 
             using (var reader = new StreamReader(stream))
@@ -55,11 +54,9 @@ public Microsoft_ML(ActivationMethod activationMethod)
                 {
                     var record = activate();
                     record.Read(i => { ReadOnlyMemory<char> s = null; getters[i](ref s); return s.ToString(); });
-                    allRecords.Add(record);
+                    yield return record;
                 }
             }
-
-            return allRecords;
         }
     }
 }