diff --git a/lib/core/macros.nim b/lib/core/macros.nim
index 22c479a4a..d3f541153 100644
--- a/lib/core/macros.nim
+++ b/lib/core/macros.nim
@@ -839,7 +839,7 @@ proc newNilLit*(): NimNode {.compileTime.} =
   ## New nil literal shortcut
   result = newNimNode(nnkNilLit)
 
-proc last*(node: NimNode): NimNode {.compileTime.} = node[<node.len]
+proc last*(node: NimNode): NimNode {.compileTime.} = node[node.len-1]
   ## Return the last item in nodes children. Same as `node[^1]`
 
 
@@ -887,7 +887,7 @@ proc newIfStmt*(branches: varargs[tuple[cond, body: NimNode]]):
 
 proc copyChildrenTo*(src, dest: NimNode) {.compileTime.}=
   ## Copy all children from `src` to `dest`
-  for i in 0 .. < src.len:
+  for i in 0 ..< src.len:
     dest.add src[i].copyNimTree
 
 template expectRoutine(node: NimNode) =
@@ -1107,7 +1107,7 @@ proc eqIdent*(node: NimNode; s: string): bool {.compileTime.} =
 proc hasArgOfName* (params: NimNode; name: string): bool {.compiletime.}=
   ## Search nnkFormalParams for an argument.
   assert params.kind == nnkFormalParams
-  for i in 1 .. <params.len:
+  for i in 1 ..< params.len:
     template node: untyped = params[i]
     if name.eqIdent( $ node[0]):
       return true
diff --git a/lib/deprecated/pure/actors.nim b/lib/deprecated/pure/actors.nim
index 36bd41e9e..be01fb3f6 100644
--- a/lib/deprecated/pure/actors.nim
+++ b/lib/deprecated/pure/actors.nim
@@ -18,7 +18,7 @@
 ##      var
 ##        a: ActorPool[int, void]
 ##      createActorPool(a)
-##      for i in 0 .. < 300:
+##      for i in 0 ..< 300:
 ##        a.spawn(i, proc (x: int) {.thread.} = echo x)
 ##      a.join()
 ##
@@ -133,7 +133,7 @@ proc createActorPool*[In, Out](a: var ActorPool[In, Out], poolSize = 4) =
   newSeq(a.actors, poolSize)
   when Out isnot void:
     open(a.outputs)
-  for i in 0 .. < a.actors.len:
+  for i in 0 ..< a.actors.len:
     a.actors[i] = spawn(poolWorker[In, Out])
 
 proc sync*[In, Out](a: var ActorPool[In, Out], polling=50) =
@@ -227,7 +227,7 @@ when not defined(testing) and isMainModule:
   var
     a: ActorPool[int, void]
   createActorPool(a)
-  for i in 0 .. < 300:
+  for i in 0 ..< 300:
     a.spawn(i, proc (x: int) {.thread.} = echo x)
 
   when false:
diff --git a/lib/pure/collections/critbits.nim b/lib/pure/collections/critbits.nim
index f70a12843..19f1f2e58 100644
--- a/lib/pure/collections/critbits.nim
+++ b/lib/pure/collections/critbits.nim
@@ -257,7 +257,7 @@ proc allprefixedAux[T](c: CritBitTree[T], key: string; longestMatch: bool): Node
       p = p.child[dir]
       if q.byte < key.len: top = p
     if not longestMatch:
-      for i in 0 .. <key.len:
+      for i in 0 ..< key.len:
         if p.key[i] != key[i]: return
     result = top
 
diff --git a/lib/pure/collections/tableimpl.nim b/lib/pure/collections/tableimpl.nim
index eec98fcaf..9a5bffcef 100644
--- a/lib/pure/collections/tableimpl.nim
+++ b/lib/pure/collections/tableimpl.nim
@@ -149,7 +149,7 @@ template delImpl() {.dirty.} =
   delImplIdx(t, i)
 
 template clearImpl() {.dirty.} =
-  for i in 0 .. <t.data.len:
+  for i in 0 ..< t.data.len:
     when compiles(t.data[i].hcode): # CountTable records don't contain a hcode
       t.data[i].hcode = 0
     t.data[i].key = default(type(t.data[i].key))
diff --git a/lib/pure/concurrency/threadpool.nim b/lib/pure/concurrency/threadpool.nim
index 0f23b7e85..01dcad9f9 100644
--- a/lib/pure/concurrency/threadpool.nim
+++ b/lib/pure/concurrency/threadpool.nim
@@ -149,7 +149,7 @@ proc selectWorker(w: ptr Worker; fn: WorkerProc; data: pointer): bool =
 proc cleanFlowVars(w: ptr Worker) =
   let q = addr(w.q)
   acquire(q.lock)
-  for i in 0 .. <q.len:
+  for i in 0 ..< q.len:
     GC_unref(cast[RootRef](q.data[i]))
     #echo "GC_unref"
   q.len = 0
@@ -543,7 +543,7 @@ proc sync*() =
   var toRelease = 0
   while true:
     var allReady = true
-    for i in 0 .. <currentPoolSize:
+    for i in 0 ..< currentPoolSize:
       if not allReady: break
       allReady = allReady and workersData[i].ready
     if allReady: break
diff --git a/lib/pure/future.nim b/lib/pure/future.nim
index 2a6d29933..f6592df71 100644
--- a/lib/pure/future.nim
+++ b/lib/pure/future.nim
@@ -22,7 +22,7 @@ proc createProcType(p, b: NimNode): NimNode {.compileTime.} =
 
   case p.kind
   of nnkPar:
-    for i in 0 .. <p.len:
+    for i in 0 ..< p.len:
       let ident = p[i]
       var identDefs = newNimNode(nnkIdentDefs)
       case ident.kind
@@ -77,7 +77,7 @@ macro `=>`*(p, b: untyped): untyped =
         if c[0].kind == nnkIdent and c[0].ident == !"->":
           var procTy = createProcType(c[1], c[2])
           params[0] = procTy[0][0]
-          for i in 1 .. <procTy[0].len:
+          for i in 1 ..< procTy[0].len:
             params.add(procTy[0][i])
         else:
           error("Expected proc type (->) got (" & $c[0].ident & ").")
@@ -96,7 +96,7 @@ macro `=>`*(p, b: untyped): untyped =
     if p[0].kind == nnkIdent and p[0].ident == !"->":
       var procTy = createProcType(p[1], p[2])
       params[0] = procTy[0][0]
-      for i in 1 .. <procTy[0].len:
+      for i in 1 ..< procTy[0].len:
         params.add(procTy[0][i])
     else:
       error("Expected proc type (->) got (" & $p[0].ident & ").")
diff --git a/lib/pure/json.nim b/lib/pure/json.nim
index fd7a3af03..3d86cc9d7 100644
--- a/lib/pure/json.nim
+++ b/lib/pure/json.nim
@@ -823,13 +823,13 @@ proc toJson(x: NimNode): NimNode {.compiletime.} =
   of nnkBracket: # array
     if x.len == 0: return newCall(bindSym"newJArray")
     result = newNimNode(nnkBracket)
-    for i in 0 .. <x.len:
+    for i in 0 ..< x.len:
       result.add(toJson(x[i]))
     result = newCall(bindSym"%", result)
   of nnkTableConstr: # object
     if x.len == 0: return newCall(bindSym"newJObject")
     result = newNimNode(nnkTableConstr)
-    for i in 0 .. <x.len:
+    for i in 0 ..< x.len:
       x[i].expectKind nnkExprColonExpr
       result.add newTree(nnkExprColonExpr, x[i][0], toJson(x[i][1]))
     result = newCall(bindSym"%", result)
@@ -1303,7 +1303,7 @@ else:
     case getVarType(x)
     of JArray:
       result = newJArray()
-      for i in 0 .. <x.len:
+      for i in 0 ..< x.len:
         result.add(x[i].convertObject())
     of JObject:
       result = newJObject()
@@ -1449,7 +1449,7 @@ proc processElseBranch(recCaseNode, elseBranch, jsonNode, kindType,
   # We need to build up a list of conditions from each ``of`` branch so that
   # we can then negate it to get ``else``.
   var cond = newIdentNode("false")
-  for i in 1 .. <len(recCaseNode):
+  for i in 1 ..< len(recCaseNode):
     if recCaseNode[i].kind == nnkElse:
       break
 
@@ -1511,7 +1511,7 @@ proc processObjField(field, jsonNode: NimNode): seq[NimNode] =
     exprColonExpr.add(getEnumCall)
 
     # Iterate through each `of` branch.
-    for i in 1 .. <field.len:
+    for i in 1 ..< field.len:
       case field[i].kind
       of nnkOfBranch:
         result.add processOfBranch(field[i], jsonNode, kindType, kindJsonNode)
@@ -1640,7 +1640,7 @@ proc createConstructor(typeSym, jsonNode: NimNode): NimNode =
         (
           var list: `typeSym` = @[];
           verifyJsonKind(`jsonNode`, {JArray}, astToStr(`jsonNode`));
-          for `forLoopI` in 0 .. <`jsonNode`.len: list.add(`constructorNode`);
+          for `forLoopI` in 0 ..< `jsonNode`.len: list.add(`constructorNode`);
           list
         )
     of "array":
@@ -1654,7 +1654,7 @@ proc createConstructor(typeSym, jsonNode: NimNode): NimNode =
         (
           var list: `typeSym`;
           verifyJsonKind(`jsonNode`, {JArray}, astToStr(`jsonNode`));
-          for `forLoopI` in 0 .. <`jsonNode`.len: list[`forLoopI`] =`constructorNode`;
+          for `forLoopI` in 0 ..< `jsonNode`.len: list[`forLoopI`] =`constructorNode`;
           list
         )
 
@@ -1683,7 +1683,7 @@ proc postProcessValue(value: NimNode): NimNode =
     result = postProcess(value)
   else:
     result = value
-    for i in 0 .. <len(result):
+    for i in 0 ..< len(result):
       result[i] = postProcessValue(result[i])
 
 proc postProcessExprColonExpr(exprColonExpr, resIdent: NimNode): NimNode =
diff --git a/lib/pure/marshal.nim b/lib/pure/marshal.nim
index c4c731acf..6ee830786 100644
--- a/lib/pure/marshal.nim
+++ b/lib/pure/marshal.nim
@@ -283,7 +283,7 @@ proc to*[T](data: string): T =
   loadAny(newStringStream(data), toAny(result), tab)
 
 when not defined(testing) and isMainModule:
-  template testit(x: expr) = echo($$to[type(x)]($$x))
+  template testit(x: untyped) = echo($$to[type(x)]($$x))
 
   var x: array[0..4, array[0..4, string]] = [
     ["test", "1", "2", "3", "4"], ["test", "1", "2", "3", "4"],
diff --git a/lib/pure/selectors.nim b/lib/pure/selectors.nim
index 506b2cec0..d17b6c253 100644
--- a/lib/pure/selectors.nim
+++ b/lib/pure/selectors.nim
@@ -162,7 +162,7 @@ elif defined(linux):
         return @[]
       raiseOSError(err)
     if evNum == 0: return @[]
-    for i in 0 .. <evNum:
+    for i in 0 ..< evNum:
       let fd = s.events[i].data.fd.SocketHandle
 
       var evSet: set[Event] = {}
@@ -253,7 +253,7 @@ elif defined(macosx) or defined(freebsd) or defined(openbsd) or defined(netbsd):
         return @[]
       raiseOSError(err)
     if evNum == 0: return @[]
-    for i in 0 .. <evNum:
+    for i in 0 ..< evNum:
       let fd = s.events[i].ident.SocketHandle
 
       var evSet: set[Event] = {}
diff --git a/lib/pure/strutils.nim b/lib/pure/strutils.nim
index 1556f7c68..f307e42c2 100644
--- a/lib/pure/strutils.nim
+++ b/lib/pure/strutils.nim
@@ -1199,7 +1199,7 @@ proc unindent*(s: string, count: Natural, padding: string = " "): string
     var indentCount = 0
     for j in 0..<count.int:
       indentCount.inc
-      if line[j .. j + <padding.len] != padding:
+      if line[j .. j + padding.len-1] != padding:
         indentCount = j
         break
     result.add(line[indentCount*padding.len .. ^1])
@@ -1407,10 +1407,10 @@ proc find*(s, sub: string, start: Natural = 0, last: Natural = 0): int {.noSideE
   ## Searching is case-sensitive. If `sub` is not in `s`, -1 is returned.
   if sub.len > s.len:
     return -1
-    
+
   if sub.len == 1:
     return find(s, sub[0], start, last)
-    
+
   var a {.noinit.}: SkipTable
   initSkipTable(a, sub)
   result = find(a, s, sub, start, last)
diff --git a/lib/pure/uri.nim b/lib/pure/uri.nim
index 4b2e4e052..c702b054c 100644
--- a/lib/pure/uri.nim
+++ b/lib/pure/uri.nim
@@ -250,7 +250,7 @@ proc combine*(base: Uri, reference: Uri): Uri =
 proc combine*(uris: varargs[Uri]): Uri =
   ## Combines multiple URIs together.
   result = uris[0]
-  for i in 1 .. <uris.len:
+  for i in 1 ..< uris.len:
     result = combine(result, uris[i])
 
 proc isAbsolute*(uri: Uri): bool =
diff --git a/lib/system/debugger.nim b/lib/system/debugger.nim
index cc6919d36..cbf977f19 100644
--- a/lib/system/debugger.nim
+++ b/lib/system/debugger.nim
@@ -127,7 +127,7 @@ proc fileMatches(c, bp: cstring): bool =
 
 proc canonFilename*(filename: cstring): cstring =
   ## returns 'nil' if the filename cannot be found.
-  for i in 0 .. <dbgFilenameLen:
+  for i in 0 ..< dbgFilenameLen:
     result = dbgFilenames[i]
     if fileMatches(result, filename): return result
   result = nil
diff --git a/lib/system/gc.nim b/lib/system/gc.nim
index 21757cf78..68bf5f6c2 100644
--- a/lib/system/gc.nim
+++ b/lib/system/gc.nim
@@ -643,9 +643,9 @@ when useMarkForDebug or useBackupGc:
         forAllChildren(d, waMarkPrecise)
 
   proc markGlobals(gch: var GcHeap) =
-    for i in 0 .. < globalMarkersLen: globalMarkers[i]()
+    for i in 0 .. globalMarkersLen-1: globalMarkers[i]()
     let d = gch.additionalRoots.d
-    for i in 0 .. < gch.additionalRoots.len: markS(gch, d[i])
+    for i in 0 .. gch.additionalRoots.len-1: markS(gch, d[i])
 
 when logGC:
   var
@@ -653,7 +653,7 @@ when logGC:
     cycleCheckALen = 0
 
   proc alreadySeen(c: PCell): bool =
-    for i in 0 .. <cycleCheckALen:
+    for i in 0 .. cycleCheckALen-1:
       if cycleCheckA[i] == c: return true
     if cycleCheckALen == len(cycleCheckA):
       gcAssert(false, "cycle detection overflow")
diff --git a/lib/system/gc2.nim b/lib/system/gc2.nim
index 6dffc323e..70bed8740 100644
--- a/lib/system/gc2.nim
+++ b/lib/system/gc2.nim
@@ -487,12 +487,12 @@ proc GC_dumpHeap*(file: File) =
   var spaceIter: ObjectSpaceIter
   when false:
     var d = gch.decStack.d
-    for i in 0 .. < gch.decStack.len:
+    for i in 0 .. gch.decStack.len-1:
       if isAllocatedPtr(gch.region, d[i]):
         c_fprintf(file, "onstack %p\n", d[i])
       else:
         c_fprintf(file, "onstack_invalid %p\n", d[i])
-  for i in 0 .. < globalMarkersLen: globalMarkers[i]()
+  for i in 0 .. globalMarkersLen-1: globalMarkers[i]()
   while true:
     let x = allObjectsAsProc(gch.region, addr spaceIter)
     if spaceIter.state < 0: break
@@ -579,7 +579,7 @@ proc markIncremental(gch: var GcHeap): bool =
   result = true
 
 proc markGlobals(gch: var GcHeap) =
-  for i in 0 .. < globalMarkersLen: globalMarkers[i]()
+  for i in 0 .. globalMarkersLen-1: globalMarkers[i]()
 
 proc doOperation(p: pointer, op: WalkOp) =
   if p == nil: return
diff --git a/lib/system/gc_ms.nim b/lib/system/gc_ms.nim
index cfc0dfa8a..272047bb7 100644
--- a/lib/system/gc_ms.nim
+++ b/lib/system/gc_ms.nim
@@ -450,9 +450,9 @@ when false:
           quit 1
 
 proc markGlobals(gch: var GcHeap) =
-  for i in 0 .. < globalMarkersLen: globalMarkers[i]()
+  for i in 0 .. globalMarkersLen-1: globalMarkers[i]()
   let d = gch.additionalRoots.d
-  for i in 0 .. < gch.additionalRoots.len: mark(gch, d[i])
+  for i in 0 .. gch.additionalRoots.len-1: mark(gch, d[i])
 
 proc gcMark(gch: var GcHeap, p: pointer) {.inline.} =
   # the addresses are not as cells on the stack, so turn them to cells:
diff --git a/lib/system/repr.nim b/lib/system/repr.nim
index 19fa564fb..102191930 100644
--- a/lib/system/repr.nim
+++ b/lib/system/repr.nim
@@ -41,7 +41,7 @@ proc `$`(x: uint64): string =
 
     let half = i div 2
     # Reverse
-    for t in 0 .. < half: swap(result[t], result[i-t-1])
+    for t in 0 .. half-1: swap(result[t], result[i-t-1])
 
 proc reprStrAux(result: var string, s: cstring; len: int) =
   if cast[pointer](s) == nil:
diff --git a/lib/system/reprjs.nim b/lib/system/reprjs.nim
index 5c265a891..12379042e 100644
--- a/lib/system/reprjs.nim
+++ b/lib/system/reprjs.nim
@@ -50,7 +50,7 @@ proc reprChar(x: char): string {.compilerRtl.} =
 
 proc reprStrAux(result: var string, s: cstring, len: int) =
   add(result, "\"")
-  for i in 0 .. <len:
+  for i in 0 ..< len:
     let c = s[i]
     case c
     of '"': add(result, "\\\"")
@@ -149,7 +149,7 @@ proc reprArray(a: pointer, typ: PNimType,
     
   {. emit: "`len` = `a`.length;\n" .}
   var dereffed: pointer = a
-  for i in 0 .. < len:
+  for i in 0 ..< len:
     if i > 0 :
       add(result, ", ")
     # advance pointer and point to element at index
@@ -192,7 +192,7 @@ proc reprRecordAux(result: var string, o: pointer, typ: PNimType, cl: var ReprCl
     reprAux(result, val, typ.node.typ, cl)
   else:
     # if the object has more than one field, sons is not nil and contains the fields.
-    for i in 0 .. <typ.node.len:
+    for i in 0 ..< typ.node.len:
       if first: first = false
       else: add(result, ",\n")
 
diff --git a/lib/system/sysstr.nim b/lib/system/sysstr.nim
index 5db16b233..0627ef2fb 100644
--- a/lib/system/sysstr.nim
+++ b/lib/system/sysstr.nim
@@ -278,7 +278,7 @@ proc setLengthSeq(seq: PGenericSeq, elemSize, newLen: int): PGenericSeq {.
                             GenericSeqSize +% (i*%elemSize)),
                             extGetCellType(result).base, waPush)
           let len1 = gch.tempStack.len
-          for i in len0 .. <len1:
+          for i in len0 ..< len1:
             doDecRef(gch.tempStack.d[i], LocalHeap, MaybeCyclic)
           gch.tempStack.len = len0
       else:
diff --git a/lib/wrappers/openssl.nim b/lib/wrappers/openssl.nim
index 5cbe2887c..431ea5912 100644
--- a/lib/wrappers/openssl.nim
+++ b/lib/wrappers/openssl.nim
@@ -593,7 +593,7 @@ from strutils import toHex, toLowerAscii
 proc hexStr(buf: cstring): string =
   # turn md5s output into a nice hex str
   result = newStringOfCap(32)
-  for i in 0 .. <16:
+  for i in 0 ..< 16:
     result.add toHex(buf[i].ord, 2).toLowerAscii
 
 proc md5_File*(file: string): string {.raises: [IOError,Exception].} =