$ works for ref|ptr|pointer for all targets (c,cpp,js,vm)

compiler/vm.nim

@@ -599,18 +599,22 @@ proc rawExecute(c: PCtx, start: int, tos: PStackFrame): TFullReg =
 
     of opcCastPtrToInt: # RENAME opcCastPtrOrRefToInt
       decodeBImm(rkInt)
+      var val = 0
       case imm
       of 1: # PtrLikeKinds
         case regs[rb].kind
         of rkNode:
-          regs[ra].intVal = cast[int](regs[rb].node.intVal)
-        of rkNodeAddr:
-          regs[ra].intVal = cast[int](regs[rb].nodeAddr)
+          let node = regs[rb].node
+          if nfIsRef in node.flags: val = cast[int](node)
+          elif node.kind == nkIntLit: val = cast[int](node.intVal)
+          else: assert false, $node.kind
+        of rkNodeAddr: val = cast[int](regs[rb].nodeAddr)
         else:
           stackTrace(c, tos, pc, "opcCastPtrToInt: got " & $regs[rb].kind)
       of 2: # tyRef
-        regs[ra].intVal = cast[int](regs[rb].node)
+        val = cast[int](regs[rb].node)
       else: assert false, $imm
+      regs[ra].intVal = val
     of opcCastIntToPtr:
       let rb = instr.regB
       let typ = regs[ra].node.typ

compiler/vmops.nim

@@ -19,6 +19,7 @@ from sighashes import symBodyDigest
 from times import cpuTime
 
 from hashes import hash
+from system/dollars import toHexImpl
 from osproc import nil
 
 import vmconv
@@ -199,6 +200,9 @@ proc registerAdditionalOps*(c: PCtx) =
   registerCallback c, "stdlib.os.getCurrentCompilerExe", proc (a: VmArgs) {.nimcall.} =
     setResult(a, getAppFilename())
 
+  registerCallback c, "stdlib.dollars.toHexImpl", proc (a: VmArgs) {.nimcall.} =
+    setResult(a, a.getInt(0).int.toHexImpl)
+
   registerCallback c, "stdlib.macros.symBodyHash", proc (a: VmArgs) {.nimcall.} =
     let n = getNode(a, 0)
     if n.kind != nkSym:

lib/pure/hashes.nim

@@ -149,21 +149,12 @@ proc hashData*(data: pointer, size: int): Hash =
   result = !$h
 
 when defined(js):
-  var objectID = 0
+  from system/dollars import getNimJsObjectID
 
 proc hash*(x: pointer): Hash {.inline.} =
   ## Efficient hashing of pointers.
   when defined(js):
-    asm """
-      if (typeof `x` == "object") {
-        if ("_NimID" in `x`)
-          `result` = `x`["_NimID"];
-        else {
-          `result` = ++`objectID`;
-          `x`["_NimID"] = `result`;
-        }
-      }
-    """
+    result = getNimJsObjectID(x)
   else:
     result = cast[Hash](cast[uint](x) shr 3) # skip the alignment
 

lib/system.nim

@@ -2051,7 +2051,7 @@ template unlikely*(val: bool): bool =
 
 
 import system/dollars
-export dollars
+export dollars except toHexImpl, getNimJsObjectID
 
 const
   NimMajor* {.intdefine.}: int = 1

lib/system/dollars.nim

@@ -65,6 +65,36 @@ else:
           return true
       return false
 
+proc c_sprintf(buf, frmt: cstring): cint {.importc: "sprintf", header: "<stdio.h>", varargs, noSideEffect.}
+
+proc toHexImpl*(x: int): string {.inline.} =
+  var buf {.noinit.}: array[int.sizeof*2+3, char] # 3 for 0x+\0
+  let num = c_sprintf(buf.addr, "%p", cast[int](x))
+  result = newString(num)
+  for i in 0..<num: result[i] = buf[i] # or memcpy
+
+when defined(js):
+  var objectID = 0
+  proc getNimJsObjectID*(x: pointer): int =
+    asm """
+      if (typeof `x` == "object") {
+        if ("_NimID" in `x`)
+          `result` = `x`["_NimID"];
+        else {
+          `result` = ++`objectID`;
+          `x`["_NimID"] = `result`;
+        }
+      }
+    """
+
+proc `$`*(x: ref|ptr|pointer): string =
+  if x == nil: "nil"
+  else:
+    template fun(): untyped = toHexImpl(cast[int](x))
+    when defined(js):
+      when nimvm: fun()
+      else: "@" & $getNimJsObjectID(cast[pointer](x))
+    else: fun()
 
 proc `$`*[T: tuple|object](x: T): string =
   ## Generic ``$`` operator for tuples that is lifted from the components

tests/system/tostring.nim

@@ -1,6 +1,8 @@
 discard """
   output: "DONE: tostring.nim"
+  targets: "c cpp js"
 """
+# xxx move this to tests/system/tdollars.nim
 
 doAssert "@[23, 45]" == $(@[23, 45])
 doAssert "[32, 45]" == $([32, 45])
@@ -46,12 +48,13 @@ const
 # ensure same result when on VM or when at program execution
 doAssert dataStr == $data
 
-import strutils
+from strutils import contains
 # array test
 
 let arr = ['H','e','l','l','o',' ','W','o','r','l','d','!','\0']
 doAssert $arr == "['H', 'e', 'l', 'l', 'o', ' ', 'W', 'o', 'r', 'l', 'd', '!', '\\x00']"
-doAssert $cstring(unsafeAddr arr) == "Hello World!"
+when not defined js: # bug
+  doAssert $cstring(unsafeAddr arr) == "Hello World!"
 
 proc takes(c: cstring) =
   doAssert c == cstring""
@@ -82,10 +85,11 @@ proc stringCompare() =
   b.add "bee"
   doAssert b == "bee"
   b.add g
-  doAssert b == "bee"
-  c.add 123.456
+  when not defined js: # bug
+    doAssert b == "bee"
+  c.addFloat 123.456
   doAssert c == "123.456"
-  d.add 123456
+  d.addInt 123456
   doAssert d == "123456"
 
   doAssert e == ""
@@ -94,7 +98,8 @@ proc stringCompare() =
   doAssert "" == ""
 
   g.setLen(10)
-  doAssert g == "\0\0\0\0\0\0\0\0\0\0"
+  when not defined(js): # bug
+    doAssert g == "\0\0\0\0\0\0\0\0\0\0"
   doAssert "" != "\0\0\0\0\0\0\0\0\0\0"
 
   var nilstring: string
@@ -103,7 +108,8 @@ proc stringCompare() =
 
 stringCompare()
 var nilstring: string
-bar(nilstring)
+when not defined(js): # bug
+  bar(nilstring)
 
 static:
   stringCompare()
@@ -116,5 +122,29 @@ block:
   s.addQuoted a2
   doAssert s == "\"fo\\\"o2\""
 
+block: # ptr-like types
+  type
+    TFoo = object
+      x1: int
+      x2: pointer
+      x3: seq[Foo]
+      x4: ptr TFoo
+    Foo = ref TFoo
+
+  template fun() =
+    doAssert $Foo.default == "nil"
+    var z = 0
+    var a = Foo(x1: 1, x2: z.addr)
+    let sa = $a
+    a.x3 = @[nil, a, Foo()]
+    a.x4 = a[].addr
+    doAssert $a.x4 == sa
+    doAssert $a.x3[0] == "nil"
+    doAssert $a.x3[1] == sa
+    doAssert $a.x3[2] != sa
+    doAssert sa in $a[]
+
+  fun()
+  static: fun()
 
 echo "DONE: tostring.nim"