rmHTMLement.nim

import std/[os, terminal, nre, math, algorithm, macros]

template  strUint( s :string) :uint=
 var res :uint
 for i, c in s:
  if c in '0'..'9': res += ((ord(c) - 48) * 10^(s.high-i)).uint
  else: raise newException(ValueError, "Non-number in string")
 res
template numChr( c :char, s: string) :uint=
 var res :uint
 for i in s:
  if i==c: inc(res)
 res
    # ML regexes           text node & comment/asymetric tag as content of text node:
let
 txNodeR= r"(?:[^<>]++(?><!--[^->]*-->|<(?>meta|link|input|img|hr|base)\b[^>]*+>)*)+"
 ctntR= r"(?:[^<>]*+(?><!--[^->]*-->|<(?>meta|link|input|img|hr|base)\b[^>]*+>)*)*+" #-> as of element node
 ctnt= re("(?s)^(" & ctntR & ")(.+)")
 nodeR= r"(<([a-z]\w*+)(?>[^/>]*+/>|[^>]*+>(?:" & ctntR & r"(?-2)*+)*+</\g-1>))"
 headR= r"(<(?>[a-z]\w*+|!DOCTYPE)[^>]*+>)"
 head= re("(?s)^" & headR & "(.+)")
var
 whole, offset, res, remain, tag :string
 totN, maxND :uint

template nodeB( tot, max, d :uint)=
 if m.isNone: return false
 let g= m.get.captures.toSeq
 inc(tot); inc(d); if d>max: max=d
 var
   tagname= g[0].get
   off = "<" & tagname
   str = g[3].get
 if g[1].isSome:
   res= off & g[1].get
   dec(d)
   if d==0:
    remain= str
    totN=tot; maxND=max
   return true
 off &= g[2].get
 while true:
   let m = str.find ctnt
   off &= m.get.captures[0]
   str= m.get.captures[1]
   if str[0..1] == "</" :
     tagname &= ">"
     if str[ 2..1+tagname.len] == tagname:
       res= off & "</" & tagname
       dec(d)
       if d==0:
        remain= str[ 2+tagname.len..^1]
        totN=tot; maxND=max
       return true
     else: break
   elif nodeRec( str):
     off &= res
     str= str[ res.len..^1]
   else: break
 return false

# 2 node functions to find direct closed tag or the nested ones, it'd count the max depth, nodes etc
# they're just header; with and without lookahead tag fed to the recursive node function inside
proc node( str= remain) :bool=
 var tot, max, d :uint
 proc nodeRec( str :string) :bool=
  let m= str.find re"(?xs) ^<([a-z]\w*+) (?> ([^/>]*+/>) | ([^>]*+>) ) (.+)"
  nodeB tot, max, d
 nodeRec str

proc node( str, tag :string) :bool=
 var tot, max, d :uint
 proc nodeRec( str :string, tag="") :bool=
  let m= str.find re("(?xs) ^<(" & tag & r"[a-z]\w*+) (?> ([^/>]*+/>) | ([^>]*+>) ) (.+)" )
  nodeB tot, max, d
 nodeRec str, tag

template getOffUp2Tag( tag="") :bool=
 let m= remain.find re(
  "(?s)^((?:" & ctntR & "(?:(?!<" & tag & r"\b)" & nodeR & ")?)*+)(?=<" & tag & r"\b)" & nodeR & "(.+)" )
 if m.isNone: false
 else:
  offset &= m.get.captures[0]
  res= m.get.captures[3]
  remain= m.get.captures[5]
  true

type
 StrPair = tuple[ Offset :string, Node :string]
 OffNodArray = seq[ StrPair]

template ctnPrevTag( nd :OffNodArray; isTheTagNode) =
 while true:
  let m= remain.find ctnt
  offset &= m.get.captures[0]
  remain = m.get.captures[1]
  if isTheTagNode:
   if maxND > minD: nd.add (offset, res)
   offset &= res
  else: break

template ctnoTagUp2Tag( nd :OffNodArray, xSpeCmd) =
 tag &= r"\b)"
 ctnPrevTag nd:
  node remain, "(?!" & tag
 tag = "(?=" & tag
 if node(remain, tag):
  if maxND > minD:
   nd.add (offset, res)
  xSpeCmd
  offset &= res
 else: break

template headeRemain( nd :string, prevOff="") =
 var m = nd.find head
 offset= prevOff & m.get.captures[0]
 remain= m.get.captures[1]

const
 isERROR  = true
 isSUCCEED= false

template posiN( posn :string, a,b :uint)=
 var
  g = posn.find(re"(?>(<)|>)(=)?(\d+)").get.captures.toSeq
  eq= g[1].isSome
  n = g[2].get.strUint       # Get a-b as lower-upper bound
 if g[0].isSome:
       b= if eq: n else: n-1
 else: a= if eq: n-1 else: n

proc getNthRev( n :var uint) :bool=
 var i :uint
 while true:
  inc(i)
  let m= remain.find re(
   "^((?:(?:" & ctntR & "(?:(?!<" & tag & r"\b)" & nodeR & ")?)*+(?=<" & tag & r"\b)" & nodeR & "){" & $i & "})" )
  if m.isNone: break
 if i<=n: return false
 n = i-n         # i is the max nth from which subtract the specified nth
 true

proc getxNRev( n :var uint) :bool=
 var i :uint
 while true:
  inc(i)
  let m= remain.find re( r"^(?:" & nodeR & "*" & txNodeR & "){" & $i & "}" )
  if m.isNone: break
 if i<=n: return false
 n= i-n
 true

template getTx_Nth( ret :OffNodArray; off, nod :string; n :uint; txNRev:bool) :bool=
 nod.headeRemain off
 if txNRev and not getxNRev( n): isERROR
 else:
  let m= remain.find re( r"^((?:" & nodeR & "*(" & txNodeR & ")){" & $n & "})" )
  if m.isNone: isERROR
  else:
   var r= m.get.captures[3]
   ret.add (offset & m.get.captures[0][0..^r.len+1], r)
   isSUCCEED

template getE_Nth( ret :OffNodArray; off, nod :string; n:uint; nthRev:bool) :bool=
 nod.headeRemain off
 if nthRev and not getNthRev( n): isERROR
 else:
  let m= remain.find re(
    r"^((?:(?:" & ctntR & "(?:(?!<" & tag & r"\b)" & nodeR & ")?)*+(?=<" & tag & r"\b)" & nodeR & "){" & $n & "})")
  if m.isNone: isERROR
  else:
   var r= m.get.captures[3]
   ret.add (offset & m.get.captures[0][0..^r.len+1], r)
   isSUCCEED

macro getTextMulN( ret :OffNodArray; off, nod, posn :string) :bool=
 result = quote do:
  `nod`.headeRemain `off`
  var a,b,i :uint
  if `posn` != "": `posn`.posiN(a,b)
  while true:
   inc(i)
   let m= remain.find re( r"^((?:" & nodeR & "*(" & txNodeR & ")){" & $i & "})" )
   if m.isNone: break
   if i>a and (b==0 or i<=b):
    var r= m.get.captures[3]
    `ret`.add (offset & m.get.captures[0][0..^r.len+1], r)
  `ret`.len==0

macro getE_MultiN( ret :OffNodArray; off, nod, posn, att :string) :bool=
 result = quote do:
  `nod`.headeRemain `off`
  var a,b,i :uint
  if `posn` != "":  `posn`.posiN(a,b)
  elif `att` != "": tag &= r"\s+" & `att`
  while true:
   if getOffUp2Tag( tag):
    inc(i)
    if i>a and (b==0 or i<=b): `ret`.add (offset, res)
    offset &= res
   else: break
  `ret`.len==0

template getE_MultiN( ret :OffNodArray; off, nod, aatt :string) :bool=
 nod.headeRemain off
 while true:
  if getOffUp2Tag( r"\S+\s+" & aatt):
   ret.add (offset, res)
   offset &= res
  else: break
 ret.len==0

template getE_MultiN( ret :OffNodArray; off, nod :string) :bool=
 nod.headeRemain off
 while true:
  if getOffUp2Tag:
    ret.add (offset, res)
    offset &= res
  else: break
 ret.len==0

template allDepthInit {.dirty.}=
 var curNode, nd= newSeqOfCap[ StrPair]( avgOffNode_Ply)
 for _ in 0..avgOffNode_Ply:
  nd.add (newStringOfCap(maxw), newStringOfCap(maxw))
  curNode.add (newStringOfCap(maxw), newStringOfCap(maxw))
 curNode.reset

template getAllDepthNth_Tx( ret :OffNodArray; off, nod :string; nth :uint; txNRev:bool) :bool=
 curNode.add (off, nod)
 while curNode.len>0:
  nd.reset
  for the in curNode:
   if getTx_Nth( ret, the.Offset, the.Node, nth, txNRev): ret.add (offset, res)
   while true:
    if getOffUp2Tag: nd.add (offset, res)
    else: break
  curNode= nd
 ret.len==0
 
template getAllDepthMultiN_Tx( ret :OffNodArray; off, nod, posn :string) :bool=
 var i,a,b:uint
 if posn != "": posn.posiN(a,b)
 curNode.add (off, nod)
 while curNode.len>0:
  nd.reset
  for the in curNode:
   while true:
    if getOffUp2Tag:
     nd.add (offset, res)
     i.inc
     if i>a and (b==0 or i<=b):
      ret.add (offset, res)
    else:
     break
  curNode= nd
 ret.len==0

template getAllDepthNth( ret :OffNodArray; off, nod :string; minD, nth :uint; nthRev, nextIsTx:bool) :bool=
 curNode.add (off, nod)
 template everyPsblNode( nthORnthRevCo) =
  while curNode.len>0:
   nd.reset
   for the in curNode:
    the.Node.headeRemain the.Offset
    nthORnthRevCo
   curNode= nd
 var i :uint
 template loopn( n:uint)=
  while true:
   inc(i)
   ctnoTagUp2Tag nd:
    if i==n and maxND >= minD: ret.add (offset, res)
 template txLoop( n:uint)=
  if getOffUp2Tag( tag):
   nd.add (offset, res)
   inc(i)
   if i==n:
    ret.add (offset, res)
   offset &= res
  else: break
 if nextIsTx:
  if nthRev:
   everyPsblNode:
    var n=nth; if getNthRev( n): n.txLoop
  else:
   everyPsblNode:
    nth.txLoop
 else:
  if nthRev:
   everyPsblNode:
    var n=nth; if getNthRev( n): n.loopn
  else:
   everyPsblNode:
    nth.loopn
 ret.len==0

template loop( commandIFoundOrBreak, i_var) =
 curNode.add (this.Offset, this.Node)
 while curNode.len>0:
  nd.reset
  for the in curNode:
   the.Node.headeRemain the.Offset
   while true:
    commandIFoundOrBreak
   i_var
  curNode=nd

# off, nod are arguments of func. of offsetNodeLoop arg. template normalization is: this.Offset, this.Node

template getAllDepthMultiN( ret :OffNodArray; off, nod :string; minD:uint; posn, att :string; nextIsTx :bool) :bool {.dirty.}=
 var a, b, i :uint
 if posn != "":  posn.posiN(a,b)
 elif att != "": tag &= r"\s+" & att
 if nextIsTx:
  loop do:
   if getOffUp2Tag( tag):
    nd.add (offset, res)
    inc(i)
    if i>a and (b==0 or i<=b):
     ret.add (offset, res)
    offset &= res
   else: break
  do: i=0
 else:
  loop do:
   ctnoTagUp2Tag nd:
    inc(i)
    if i>a and (b==0 or i<=b) and maxND >= minD:
     ret.add (offset, res)
  do: i=0
 ret.len==0
 
template getAllDepthMultiN( ret :OffNodArray; o, n :string; minD :uint; aatt :string; nextIsTx :bool) :bool {.dirty.}=
 tag = r"\S+\s+" & aatt
 loop do:
  ctnoTagUp2Tag nd:
   if maxND >= minD: ret.add (offset, res)
 do:discard
 ret.len==0

template getAllDepthMultiN( ret :OffNodArray; o, n :string; minD :uint; nextIsTx :bool) :bool {.dirty.}=
 tag = ""
 loop do:
  ctnoTagUp2Tag nd:
   if maxND >= minD: ret.add (offset, res)
 do:discard
 ret.len==0

template offsetNodeLoop( xPathPat) =
 for i, this {.inject.} in offsetNode:
  retOffNode.reset
  if xPathPat:
   if i<offsetNode.high: continue         # if it's not the last in loop, go on iterating, otherwise
   return resultArr.len==0                # return true (1) if finding none or false if finding any
  if not isTxNode and
   remPath.len>0:
    let e= getE_Path_R( remPath, retOffNode)    #...is propagating to the next depth and returning boolean
    if i==offsetNode.high: return e             # value which'll be returned if this's the last iteration 
  else:
   resultArr.add retOffNode

var
 avgOffNode_Ply, maxw :uint
 resultArr :OffNodArray

proc getE_Path_R( path :string; offsetNode :OffNodArray) :bool=
 var
  g= path.find(re"(?x)^/ (/)? (?> (text\(\)) (?: \[ (?> (last\(\)-)? ([1-9]\d*+) | position\(\) (?!<1) ([<>]=? [1-9]\d*+)) \])? | (?> ([^/@*[]+) (?: \[ (?> (?>(last\(\)-)|position\(\)=)? ([1-9]\d*+) | position\(\) (?!<1) ( [<>]=? [1-9]\d*+ ) | @(\*| [^]]+) ) \] )? | @([a-z]\w*[^/]* |\*) | (\*) ) (.*)  )" ).get.captures.toSeq
  nth, txNth :uint
  txPos, posn, attg, aatt :string
  remPath= g[12].get
  minD= 1 + numChr( '/', remPath)
  retOffNode= newSeqOfCap[ StrPair]( avgOffNode_Ply)       # the offset-node pair found which...
 for _ in 0..avgOffNode_Ply:
  retOffNode.add (newStringOfCap(maxw),newStringOfCap(maxw))
 template isAllDepths:bool= g[0].isSome
 template isTxNode   :bool= g[1].isSome
 template txNRev     :bool= g[2].isSome
 template isTxNth:bool= g[3].isSome
 template isTxPos:bool= g[4].isSome
 template isTag  :bool= g[5].isSome
 template nthRev :bool= g[6].isSome
 template isNth  :bool= g[7].isSome
 template isPosn :bool= g[8].isSome
 template isAttg :bool= g[9].isSome
 template isAatt :bool= g[10].isSome
 template nextPly_Tx :bool= remPath.find(re"^//?text\(\)").isSome
 if isTxNode:
  if isTxNth: txNth= g[3].get.strUint
  elif isTxPos: txPos= g[4].get
 elif isTag:
  tag= g[5].get
  if isNth:
   nth= g[7].get.strUint
  elif isPosn:
   posn= g[8].get
  elif isAttg:
   attg= g[9].get
 elif isAatt:
  aatt= g[10].get
 if isAllDepths:              # all depths under current //
  allDepthInit
  if isTag:
   if isNth:
    offsetNodeLoop: getAllDepthNth retOffNode, this.Offset, this.Node, minD, nth, nthRev, nextPly_Tx
   else:
    offsetNodeLoop: getAllDepthMultiN retOffNode, this.Offset, this.Node, minD, posn, attg, nextPly_Tx
  elif isAatt:
   offsetNodeLoop: getAllDepthMultiN retOffNode, this.Offset, this.Node, minD, aatt=aatt, nextPly_Tx
  elif isTxNode:
   if isTxNth:
    offsetNodeLoop: getAllDepthNth_Tx retOffNode, this.Offset, this.Node, txNth, txNRev
   else:
    offsetNodeLoop: getAllDepthMultiN_Tx retOffNode, this.Offset, this.Node, txPos
  else:
   offsetNodeLoop: getAllDepthMultiN retOffNode, this.Offset, this.Node, minD, nextPly_Tx
 elif isTag:
  if isNth:
   offsetNodeLoop: getE_Nth retOffNode, this.Offset, this.Node, nth, nthRev
  else:
   offsetNodeLoop: getE_MultiN retOffNode, this.Offset, this.Node, posn, attg
 elif isAatt:
  offsetNodeLoop: getE_MultiN retOffNode, this.Offset, this.Node, aatt
 elif isTxNode:
  if isTxNth:
   offsetNodeLoop: getTx_Nth retOffNode, this.Offset, this.Node, txNth, txNRev
  else:
   offsetNodeLoop: getTextMulN retOffNode, this.Offset, this.Node, txPos
 else:
  offsetNodeLoop: getE_MultiN retOffNode, this.Offset, this.Node
 # be any of these true, it failed finding. Now see if
 isSUCCEED

var
 aCP, outf :string
 paths :seq[ string]
template xPathsCheck( path:string; hasTarget="")=
 paths.reset
 for p in path.split re"[|;]":
  if p.contains xpath:
    if p.contains re"^[^/]":
      if aCP.len == 0:
       echo "\n'",p,"' is relative to base/current path which is empty"
       while true:
        echo "\nPut a valid one: "
        aCP = readLine(stdin).replace( re"\h+", "")
        if aCP.contains xpath: break
        echo "\n'",aCP,"' is not a valid Xpath"
      aCP &= "/"
      var pr= p.replace( re"^\./", "")
      while pr.contains(re"^\.\.") :
        if aCP == "/" : echo "\n'", pr,"' upward node ..\nran over '",aCP,"' current path";quit(0)
        aCP = aCP.replace( re"[^/]+/$", "")
        pr = pr.replace( re"^../?", "")
      paths.add( aCP & pr)
    else: paths.add( p)
  else:
   echo "\n'",p,"' is invalid Xpath\nSkip? (s: skip. else: abort): "
   if getch() != 's': echo "\nAborting";quit(1)
 let totPaths {.inject.}= paths.len.uint
 if totPaths==0: quit("\nNo valid xpath " & hasTarget,0)

template getDocFile( f :string)=
 f.getDocFile(whole)
template getDocFile( f, w :string)=
 while true:
  if fileExists(f):
   try: w = readFile f
   except IOError as e:
    echo "\nCannot read '",f,"': ",e.msg
    continue
   except OverflowDefect as e:
    echo e.msg;continue
   except:
    echo "\nFile '",outf,"': critical error";continue
   finally:break
  else:
   echo "'",f,"' doesn't exist"
  while true:
   stdout.write "Try another file name:"
   f=readLine(stdin).replace(re"^\h+|\s+$", "")
   if f.len>0: break

template validatingML= validatingML whole
template validatingML( w :string)=
 let m= w.find re(
  r"(?xs)^(\s* (?: <\?xml\b [^>]*+> \s* )?) (< (!DOCTYPE) [^>]*+> [^<]* (.+))" )
 if m.isNone or
  not m.get.captures[3].node or (let r=remain.replace(re"^\s+|\s+$",""); r).len>0 and
  not r.contains(re( r"\s*(?:" & nodeR & ")*")):
   echo "\nCan't parse it due to mark-up language's ill-form or unbalanced tag pair\nAborting"
   quit(0)
 iniNode= @[(m.get.captures[0], m.get.captures[1] & "</" & m.get.captures[2] & ">")]

template path_search_H=
 avgOffNode_Ply= (totN.float / maxND.float * 1.5 ).uint
 miss = newSeqOfCap[ string ](totPaths)
 let maxFouND = (totN.float * 3 / 4).uint
 fpath= newSeqOfCap[ StrPair ](maxFouND)
 maxw= (whole.len-17).uint
 offset= newStringOfCap(maxw)
 res   = newStringOfCap(maxw)
 remain= newStringOfCap(maxw)
 for _ in 0..maxFouND:
  resultArr.add (newStringOfCap(maxw), newStringOfCap(maxw))
  fpath.add (newStringOfCap(maxw), newStringOfCap(maxw))
 for _ in 0..totPaths:
  pathResult.add (newStringOfCap(71), fpath)

template path_search_B( asTarget="")=
 template unsortRes( fnd)=
  foundd=""
  for i in pathResult:
   foundd &= "\n" & i[0] & ":"
   for j{.inject.} in i[1]:
    foundd &= "\n-----\n" & j.Node
    fnd
 fpath.reset
 pathResult.reset
 var fail :bool
 paths.sort( proc( a,b :string) :int= cmp(a.len, b.len) )
 for aPath in paths:
  if fail:
   echo "Skipping it, searching for the next path"
  resultArr.reset
  fail= getE_Path_R( aPath, iniNode)
  if fail:
   miss.add aPath; echo "Can't find:\n",aPath
  else:
   pathResult.add (aPath, resultArr)       # tuple of each path's array of offset-node found
   block F:
    for s in short:         # filter out duplicate path or path whose head as the same as shorter one's
     if aPath.contains(re(r"^\Q" & s & r"\E")): break F
    fpath.add(resultArr)
   short.add aPath
 if miss.len>0:
  if pathResult.len>0:
    echo "\nSkip every unfound path and keep going for the found ones? (y: Yes. else key: Abort) "
    if getch()=='y':
     echo "To process every path"
     for p in pathResult:
      echo "\n",p[0]
    else: quit("\nAborting",0)
  else: quit("\nNothing was done" & asTarget,0)
 else: stdout.write "Every given path was "
 if asTarget=="":
      unsortRes: founds &= j.Node
 else:unsortRes: discard

template each_path_search( file :string; asTarget="")=
 file.getDocFile
 echo "Checking document '",file,"'... "
 validatingML()
 path_search_H
 path_search_B( asTarget)
 echo "found on document '",file,"'",asTarget,"\nEvery element of it:\n",foundd

######   main   ######
let
 xpath= re"(?x) ^(?> /?/? ( ([a-z]\w*+) (?:\[ (?> (?:last\(\)-)? [0-9]\d*+ | position\(\) (?!<1)[<>]=? [0-9]\d*+ | @((?>(?2)(?:=(?2))? | \*)) ) \])? | @(?-1) | \*) | \.\.?) (?://?(?1))* (?: //?text\(\) (?: \[ (?> (?:last\(\)-)? [1-9]\d*+ | position\(\) (?!<1) [<>]=? [1-9]\d*+) \])? )? $"
var
 cmdLine= commandLineParams()
 (pathStr, srcFile)= if cmdLine.len>0:    # This block expectedly errs and need a knowledgable one's
  echo "\nTry to accomplish:"             # colloboration to correct it
  for i,l in cmdLine:
   echo i,". ",l
  var
   op= cmdLine[1]
   l = cmdLine[0]
  (cmdLine[2], cmdLine[3])
 else:
   echo "Element path is of Xpath form e.g:\n\thtml/body/div[1]//div[1]/div[2]\nmeans find in a given HTML or XML file, the second div tag element that is under the first\ndiv element anywhere under the first div element, under any body element,\nunder any html element.\n\nTo put multiply at once, put one after another delimited by ; or |. Put in two data,\nFirst, the element path. Copy operation may be as source then target delimited by '+>'\nSecond, the HTML/XML file name :\n"
   (readLine(stdin), readLine(stdin)) 
if pathStr.len==0: quit("\nNo Xpath given",0)

let srdPaths= pathStr.replace(re"\h+", "").split(re"\+>")
srdPaths[0].xPathsCheck
var
 pathResult = newSeqOfCap[ (string, OffNodArray) ](totPaths)        # Preallocation
 miss :seq[ string ]
 short :seq[ string ]
 fpath, iniNode :OffNodArray
 opt :char
 founds, foundd :string
block:                          # scope to get around equivalent C++ delete command with hope
 srcFile.each_path_search       # once exiting it, any allocation inside gets freed by Nim GC
if cmdLine.len==0:
 opt= if srdPaths.len>1:'c'
 else:
  echo "\nWhich operation would be done:\n- Remove\n- Copy\n- Save to file or quit\n( r: Remove. c: Copy. Else key: Save or quit )"
  getch()

case opt
of 'c','C':
 var dstPath= if srdPaths.len==1:
  echo "\nPut target element, in xpath form:"; readLine(stdin)
 else: srdPaths[1]
 dstPath.xPathsCheck : "of copy target"
 echo "\nSpecify the copy target file (Enter: as the same as the source):"
 var dstFile=readLine(stdin)
 if dstFile != "":
  dstFile.each_path_search: " to copying"
 else:
  path_search_B: " to copying"
  echo "found as copy target in the same document '",srcFile,"'\nEvery element of it:\n",foundd
 fpath.sort( proc( a,b :StrPair) :int=cmp( b.Offset.len, a.Offset.len) )
 echo "Should source element be under target element, replacing it, preceding it, or following it?\n(u: Under it. r: Replacing it. p: Preceding it. else key: Following it)"
 case getch()
 of 'u','U':
  for on in fpath:
   whole= whole.replace(re(
    r"^\Q" & on.Offset & r"\E" & headR), "$0" & founds)
 of 'r','R':
  for on in fpath:
   whole= whole.replace(re(
    r"^(\Q" & on.Offset & r"\E)" & nodeR), "$1" & founds)
 of 'p','P':
  for on in fpath:
   whole= whole.replace(re(
    r"^\Q" & on.Offset & r"\E"), "$0" & founds)
 else:
  for on in fpath:
   whole= whole.replace(re(
    r"^\Q" & on.Offset & on.Node & r"\E"), "$0" & founds)
 echo "\nCopying result:\n",whole
of 'r','R':
 fpath.sort( proc( a,b :StrPair) :int=cmp( b.Offset.len, a.Offset.len) )
 for on in fpath:
  whole= whole.replace(re(r"(?s)^(\Q" & on.Offset & r"\E)\Q" & on.Node & r"\E(.*)"), "$1$2")
 echo "\nRemoval result:\n",whole
else: whole=founds
echo "Save to a file? (y: Yes, save. else key: Quit)"
if getch()=='y':
 while true:
  echo "File name to save:"
  outf=readLine(stdin).replace(re"^\h+|\s+$", "")
  if outf.len>0:
   if fileExists(outf):
    echo "There is file name '",outf,"'\nOverwrite it (y: Yes. Else key: No) ?"
    if getch() != 'y':
     echo "\nNot overwrite it"
   else:
    try: writeFile(outf,whole)
    except IOError as e:
     echo "\nCannot write to '",outf,"': ",e.msg
     continue
    except:
     echo "\nFile '",outf,"': critical error"
     continue
    finally:break
 echo "Successfully saved to '",outf,"'"