start of tests refactoring; sqlite3 new wrapper fixes

tests/accept/compile/tcolors.nim

@@ -0,0 +1,39 @@
+import strutils
+
+type
+  TColor = distinct int32
+
+proc rgb(r, g, b: range[0..255]): TColor = 
+  result = TColor(r or g shl 8 or b shl 16)
+
+proc `$`(c: TColor): string =
+  result = "#" & toHex(int32(c), 6)
+
+echo rgb(34, 55, 255)
+
+when false:
+  type
+    TColor = distinct int32
+    TColorComponent = distinct int8
+  
+  proc red(a: TColor): TColorComponent = 
+    result = TColorComponent(int32(a) and 0xff'i32)
+  
+  proc green(a: TColor): TColorComponent = 
+    result = TColorComponent(int32(a) shr 8'i32 and 0xff'i32)
+  
+  proc blue(a: TColor): TColorComponent = 
+    result = TColorComponent(int32(a) shr 16'i32 and 0xff'i32)
+  
+  proc rgb(r, g, b: range[0..255]): TColor = 
+    result = TColor(r or g shl 8 or b shl 8)
+  
+  proc `+!` (a, b: TColorComponent): TColorComponent =  
+    ## saturated arithmetic:
+    result = TColorComponent(min(ze(int8(a)) + ze(int8(b)), 255))
+  
+  proc `+` (a, b: TColor): TColor = 
+    ## saturated arithmetic for colors makes sense, I think:
+    return rgb(red(a) +! red(b), green(a) +! green(b), blue(a) +! blue(b))
+  
+  rgb(34, 55, 255)