From efe51f129f6f08f03ca9fcf718ac7ecd9292ee12 Mon Sep 17 00:00:00 2001
From: Sun Serega <sunserega2@gmail.com>
Date: Sun, 31 Mar 2024 14:30:21 +0200
Subject: [PATCH] cleanup TODO's

---
 Fixers.pas                 |  2 +-
 Patterns.pas               |  3 --
 Patterns/MergedStrings.pas |  5 ++-
 Patterns/test.pas          |  4 +--
 SubExecuters.pas           |  2 --
 TypeMagic.pas              | 68 ++++++++++++++++++++++++++++++++++++++
 6 files changed, 73 insertions(+), 11 deletions(-)
 create mode 100644 TypeMagic.pas

diff --git a/Fixers.pas b/Fixers.pas
index b96fae5d..4dfc97ea 100644
--- a/Fixers.pas
+++ b/Fixers.pas
@@ -53,7 +53,7 @@ interface
       var start := true;
       var bl_start := true;
       
-      //TODO #2683
+      //TODO #2715
       var make_res: function: (array of string,array of string) := ()->
       begin
         var lc := res.Count;
diff --git a/Patterns.pas b/Patterns.pas
index f884fee3..7c9ce696 100644
--- a/Patterns.pas
+++ b/Patterns.pas
@@ -1,9 +1,6 @@
 unit Patterns;
 {$zerobasedstrings}
 
-//TODO #2739
-{$savepcu false}
-
 interface
 
 uses System;
diff --git a/Patterns/MergedStrings.pas b/Patterns/MergedStrings.pas
index acab1d7c..afe13026 100644
--- a/Patterns/MergedStrings.pas
+++ b/Patterns/MergedStrings.pas
@@ -529,7 +529,7 @@ implementation
     private parts: array of MergedStringPart;
     private len_caps: array of MergedStringLength;
     
-    private constructor(parts: array of MergedStringPart);
+    private constructor(params parts: array of MergedStringPart);
     begin
       self.parts := parts;
       SetLength(len_caps, parts.Count);
@@ -675,8 +675,7 @@ implementation
 function MergedStringPointer.IsOut := data.part_i = s.parts.Length;
 
 static function MergedString.Literal(s: string) :=
-//TODO #3064: adding params breaks case where array is passed to "new MergedString"
-new MergedString(new MergedStringPart[](new MergedStringPartSolid(s)));
+new MergedString(new MergedStringPartSolid(s));
 
 static function MergedString.Parse(s: StringSection; escape_sym: char) :=
 new MergedString(OptimizeParts(MakeParts(s, escape_sym)).ToArray);
diff --git a/Patterns/test.pas b/Patterns/test.pas
index 104e569a..a0aca4c9 100644
--- a/Patterns/test.pas
+++ b/Patterns/test.pas
@@ -37,9 +37,9 @@
 
 var p: MergedString;
 begin
-  var ps := EnumerateFiles('G:/0Prog/AutoMaximize/Classes/1 What')
+  var ps := EnumerateFiles('G:\0Prog\AutoMaximize\Classes\1 What')
     .Select(System.IO.Path.GetFileName)
-    .Where(fname->fname.StartsWith('HwndWrapper'))
+//    .Where(fname->fname.StartsWith('HwndWrapper'))
     .Select(MergedString.Literal)
     .ToHashSet;
   while ps.Count.Println>1 do
diff --git a/SubExecuters.pas b/SubExecuters.pas
index 6dc573cf..4bb92537 100644
--- a/SubExecuters.pas
+++ b/SubExecuters.pas
@@ -7,8 +7,6 @@
 uses PathUtils;
 uses Timers;
 
-uses AQueue; //TODO #2543
-
 {$region Helpers}
 
 type
diff --git a/TypeMagic.pas b/TypeMagic.pas
new file mode 100644
index 00000000..fc72491a
--- /dev/null
+++ b/TypeMagic.pas
@@ -0,0 +1,68 @@
+unit TypeMagic;
+
+interface
+
+type
+  
+  {$region Convert}
+  
+  ConvertTo<T> = sealed class
+    
+    private constructor := raise new System.InvalidOperationException;
+    
+    public static function FromChecked<T2>(o: T2): T;
+    public static function FromUnchecked<T2>(o: T2): T;
+    public static function From<T2>(o: T2; checked: boolean := true) :=
+      if checked then FromChecked(o) else FromUnchecked(o);
+    
+  end;
+  
+  {$endregion Convert}
+  
+implementation
+
+uses System.Linq.Expressions;
+
+{$region Convert}
+
+type ConvertCache<T1,T2> = sealed class
+  
+  private constructor := raise new System.InvalidOperationException;
+  
+  public static checked, unchecked: T2->T1;
+  private static function MakeFunc(conv: (Expression,System.Type)->Expression): T2->T1;
+  begin
+    try
+      var p := Expression.Parameter(typeof(T2));
+      var c := conv(p, typeof(T1));
+      var l := Expression.Lambda&<Func<T2, T1>>(c, p);
+      Result := l.Compile();
+    except
+      on e: Exception do
+      begin
+        Result := o->
+        begin
+          Result := default(T1);
+          raise new System.InvalidCastException($'Failed to make [{TypeToTypeName(typeof(T2))}]=>[{TypeToTypeName(typeof(T1))}] conversion', e);
+        end;
+        exit;
+      end;
+    end;
+    
+  end;
+  static constructor;
+  begin
+    checked := MakeFunc(Expression.ConvertChecked);
+    unchecked := MakeFunc(Expression.Convert);
+  end;
+  
+end;
+
+static function ConvertTo<T>.FromChecked<T2>(o: T2) :=
+  ConvertCache&<T,T2>.checked(o);
+static function ConvertTo<T>.FromUnchecked<T2>(o: T2) :=
+  ConvertCache&<T,T2>.unchecked(o);
+
+{$endregion Convert}
+
+end.
\ No newline at end of file