diff --git a/modules/gmt/modgmt_map.cpp b/modules/gmt/modgmt_map.cpp
index c0f71c4..d35f064 100644
--- a/modules/gmt/modgmt_map.cpp
+++ b/modules/gmt/modgmt_map.cpp
@@ -61,13 +61,9 @@ Resulted shift is added to own shift of layer (setted by function LayerShift).
 */
 const ObjectBase* GMT_Map(const ObjectList* input)
 {
- const ObjectList* list=input;
- auto size=list->Size();
- if(0==size) return 0;
- decltype(size) pos=0;
+ std::string err;
  std::string title;
- std::stack<std::pair<const ObjectList*,decltype(pos)> > lstack;
- bool first=true;
+
  double xg,yg,x,y;
  bool xislocal=false, yislocal=false;
  std::list<std::shared_ptr<std::string> > data;
@@ -78,45 +74,29 @@ const ObjectBase* GMT_Map(const ObjectList* input)
  // See http://bugs.ghostscript.com/show_bug.cgi?id=202735
  data.emplace_back(new std::string("4000 4000 translate"));
  data.emplace_back(new std::string(header));
- while(pos<size)
+ for(auto i=input->begin(); i!=input->end(); ++i)
  {
-  // Check if next argument is list
-  {
-   OBType<ObjectList> l(list->At(pos));
-   // Descending
-   if(l)
-   {
-    if(0==l->Size()) goto next;
-    lstack.push(std::make_pair(list,pos));
-    list=l;
-    pos=0;
-    size=l->Size();
-    continue;
-   }
-  }
-
   // Check if first argument is string
-  if(first)
+  if(input->begin()==i)
   {
-   first=false;
-   OBType<ObjectString> s(list->At(pos));
+   OBType<ObjectString> s(*i);
    if(s)
    {
     title=s->Value();
-    goto next;
+    continue;
    }
   }
 
   // Check if argument is pair
   {
-   OBType<ObjectPair> p(list->At(pos));
+   OBType<ObjectPair> p(*i);
    if(p)
    {
     std::string name=p->Name();
     tolower(name);
-    Base2Double d(p->Value());
+    Base2Double d;
     bool suc=true;
-    double val=d(&suc);
+    double val=d.Convert(p->Value(),&suc,err);
     if(!suc) goto fail; // Conversion failed
     suc=false;
     if("x"==name) {suc=true; xislocal=true; x=val;}
@@ -127,14 +107,14 @@ const ObjectBase* GMT_Map(const ObjectList* input)
     if("yg"==name) {suc=true; yg=val;}
     if("xgr"==name) {suc=true; xg+=val;}
     if("ygr"==name) {suc=true; yg+=val;}
-    if(!suc) goto fail; // Unknown name
-    goto next;
+    if(!suc) {err="Unknown parameter name: "+p->Name(); goto fail;} // Unknown name
+    continue;
    }
   }
 
   // Check if argument is layer
   {
-   OBType<ObjectGMTLayer> l(list->At(pos));
+   OBType<ObjectGMTLayer> l(*i);
    if(l)
    {
     struct gmt_layer layer=l->Data();
@@ -148,22 +128,11 @@ const ObjectBase* GMT_Map(const ObjectList* input)
      data.emplace_back(new std::string(layer.EndShift()));
     }
     else data.emplace_back(layer.data);
-    goto next;
+    continue;
    }
   }
-
+  err="Unknown argument type: "+i->Type();
   goto fail; // Unknown type of argument
-  next:
-  pos++;
-  // Ascending
-  if(pos==size && !lstack.empty())
-  {
-   list=lstack.top().first;
-   pos=lstack.top().second;
-   lstack.pop();
-   size=list->Size();
-   goto next;
-  }
  }
  data.emplace_back(new std::string(footer));
 
@@ -175,7 +144,7 @@ const ObjectBase* GMT_Map(const ObjectList* input)
   int ret;
 
   ret=GhostRun("-sDEVICE=bbox",gs_bbox_callback,&in,0,&bboxes,0); // Bounding box is writed on stderr
-  if(0!=ret) goto fail; // Something wrong
+  if(0!=ret) {err="Can't determine BoundingBox"; goto fail;} // Something wrong
 
   std::smatch m;
   std::smatch::const_iterator ci;
@@ -183,7 +152,7 @@ const ObjectBase* GMT_Map(const ObjectList* input)
   bool ok=true;
 
   std::regex_search(bboxes,m,r);
-  if(5!=m.size()) goto fail; // This is strange and scary
+  if(5!=m.size()) {err="Something go wrong, this is strange and scary"; goto fail; }// This is strange and scary
   ci=m.cbegin();
   ci++; // Skip full match
 
@@ -191,7 +160,7 @@ const ObjectBase* GMT_Map(const ObjectList* input)
   ok=ok && str2int(*ci++,&bbly);
   ok=ok && str2int(*ci++,&bbrx);
   ok=ok && str2int(*ci++,&bbry);
-  if(!ok) goto fail; // Unexpected!
+  if(!ok) {err="Unexpected error!"; goto fail;} // Unexpected!
   // FIXME: Workaround ghostscript bug 202735
   // We add 5 points to each margin because ghostscript does'nt count linewidths when calculate bounding box
   bblx-=4005;
@@ -224,7 +193,7 @@ const ObjectBase* GMT_Map(const ObjectList* input)
  }
 
  fail:
- return 0;
+ return new ObjectError("Map",err);
 }
 
 // Creating pdf from eps
@@ -235,39 +204,24 @@ Optionally, resolution can be specified by pair with name resolution, res or r a
 */
 const ObjectBase* GMT_Convert2PDF(const ObjectList* input)
 {
- if(!gs_abilities.havepdf) return 0; // No pdf support
- double r;
- bool suc=true;
- const ObjectGMTMap* map=0;
+ std::string err;
+ RNFPar<SearchGMTMap,ObjectGMTMap> map("map");
+ ONPar<Base2PosD> r("resolution",720);
+ ParseNamedParameters params(input,map,r);
+ const ObjectGMTMap* m=map;
 
- {
-  SearchParameterWDefO<double,DoubleDefaultVal<720>,false,PMin<1> > res(input,"r","res","resolution");
-  r=res(&suc);
-  if(!suc) goto fail; // Error
- }
-
- {
-  for(ObjectList::IndexType i=0;i<input->Size();i++)
-  {
-   OBType<ObjectGMTMap> m(input->At(i));
-   if(m)
-   {
-    if(0!=map) goto fail; // Duplicate
-    map=m;
-   }
-  }
-  if(0==map) goto fail; // Map not found
- }
+ if(!gs_abilities.havepdf) {err="No PDF support in Ghostscript"; goto fail;} // No pdf support
+ if(!params) {err=params.Error(); goto fail;} // Parsing error
 
  {
   std::string* out=new std::string;
-  int ret=eps2pdf(*(map->pValue()),out,r);
-  if(0!=ret) { delete out; goto fail; } // Something wrong
-  return new ObjectGMTMapPDF(out,map->Bblx(),map->Bbly(),map->Bbrx(),map->Bbry());
+  int ret=eps2pdf(*(m->pValue()),out,r);
+  if(0!=ret) {err="Conversion of EPS to PDF failed"; delete out; goto fail; } // Something wrong
+  return new ObjectGMTMapPDF(out,m->Bblx(),m->Bbly(),m->Bbrx(),m->Bbry());
  }
 
  fail:
- return 0;
+ return new ObjectError("EPS2PDF",err);
 }
 
 
@@ -286,112 +240,101 @@ antialiasing or aa - can be used to set graphics and text antialiasing simultane
 */
 const ObjectBase* GMT_Convert2PNG(const ObjectList* input)
 {
- if(!gs_abilities.havepdf) return 0; // No pdf support, so, no png
- double r;
- bool suc=true;
- const GMTMap* map=0;
- std::string gsdev("");
- bool ispdf;
- uint aat=0,aag=0;
- std::string aats("full"),aags("full");
- uint dscale=0;
-
- // Map to convert
+ std::string gsdev,err;
+ double res;
+
+ ONPar<Base2PosD> r("resolution",300),ds("d[own]scale",1.0);
+ ONPar<Base2Pos> w("width"),h("height");
+ ONPar<Base2StringD> cs("c[olor][ ]space","color"),taa("t[ext]a[nti]aliasing","full"),gaa("g[raphics]a[nti]aliasing","full"),aa("a[nti]aliasing","full");
+ const ObjectGMTMap* me;
+ const ObjectGMTMapPDF* mp;
+ const GMTMap* m;
+ uint aat,aag;
+ uint dscale;
+
+ if(!gs_abilities.havepdf) {err="No PDF support in Ghostscript"; goto fail;} // No pdf support, so, no png
+ // Search map
  {
-  for(ObjectList::IndexType i=0;i<input->Size();i++)
-  {
-   OBType<ObjectGMTMap> m(input->At(i));
-   OBType<ObjectGMTMapPDF> p(input->At(i));
-   if(m)
-   {
-    if(0!=map) goto fail; // Duplicate
-    map=m;
-    ispdf=false;
-   }
-   if(p)
-   {
-    if(0!=map) goto fail; // Duplicate
-    map=p;
-    ispdf=true;
-   }
-  }
-  if(0==map) goto fail; // Map not found
+  RNFPar<SearchGMTMap,ObjectGMTMap> mapeps("map");
+  RNFPar<SearchGMTMapPDF,ObjectGMTMap> mappdf("map");
+  ParseNamedParameters peps(input,mapeps);
+  ParseNamedParameters ppdf(input,mappdf);
+  if(!(peps || ppdf)) {err="Error parsing map parameter"; goto fail;}
+  me=mapeps; mp=mappdf;
+  if(nullptr==me && nullptr==mp) {err="Map parameter not specified"; goto fail;} // This must never happened
+  if(nullptr!=me) m=me; else m=mp;
+ }
+ // Parse other parameters
+ {
+  ParseNamedParameters params(input,r,ds,w,h,cs,taa,gaa,aa);
+  if(!params) {err=params.Error(); goto fail;}
  }
 
  // Determine resolution
  {
-  SearchParameter<double,false,PMin<1> > res(input,"r","res","resolution");
-  BaseM2Double w(input,"width","w"), h(input,"height","h");
   // Check existence
-  if( ( res.Exist() && w.Exist() ) || ( res.Exist() && h.Exist() ) || ( w.Exist() && h.Exist() )) goto fail; // Only one parameter allowed
-  r=300; // Default value
-  if(res.Exist()) r=res(&suc);
-  if(w.Exist()) r=w(&suc)*72.0/(map->Bbrx()-map->Bblx());
-  if(h.Exist()) r=h(&suc)*72.0/(map->Bbry()-map->Bbly());
-  if(!suc) goto fail; // Error
+  if( ( r.Exist() && w.Exist() ) || ( r.Exist() && h.Exist() ) || ( w.Exist() && h.Exist() )) {err="Only one of resolution, width or height may be specified"; goto fail;} // Only one parameter allowed
+  if(r.Exist()) res=r;
+  if(w.Exist()) res=w*72.0/(m->Bbrx()-m->Bblx());
+  if(h.Exist()) res=h*72.0/(m->Bbry()-m->Bbly());
  }
 
  // Color model
  {
-  std::string cs;
-  BaseMD2String cspace(input,"8bit","colorspace","cspace","cs");
-  cs=cspace(&suc);
-  if(!suc) goto fail; // Error
-  tolower(cs);
-  if(("mono"==cs || "monochrome"==cs) && gs_abilities.havepngmono) gsdev="pngmono";
-  if(("monod"==cs || "monodiffused"==cs) && gs_abilities.havepngmonod) gsdev="pngmonod";
-  if(("16c"==cs || "16"==cs) && gs_abilities.havepng16) gsdev="png16";
-  if(("256c"==cs || "256"==cs) && gs_abilities.havepng256) gsdev="png256";
-  if(("gray"==cs || "grey"==cs || "g"==cs) && gs_abilities.havepnggray) gsdev="pnggray";
-  if(("full"==cs || "8bit"==cs || "color"==cs) && gs_abilities.havepng16m) gsdev="png16m";
-  if(""==gsdev) goto fail; // Incorrect value
+  std::string cspace=cs;
+  tolower(cspace);
+  if(("mono" ==cspace || "monochrome"  ==cspace                   ) && gs_abilities.havepngmono)  gsdev="pngmono";
+  if(("monod"==cspace || "monodiffused"==cspace                   ) && gs_abilities.havepngmonod) gsdev="pngmonod";
+  if(("16c"  ==cspace || "16"          ==cspace                   ) && gs_abilities.havepng16)    gsdev="png16";
+  if(("256c" ==cspace || "256"         ==cspace                   ) && gs_abilities.havepng256)   gsdev="png256";
+  if(("gray" ==cspace || "grey"        ==cspace || "g"    ==cspace) && gs_abilities.havepnggray)  gsdev="pnggray";
+  if(("full" ==cspace || "8bit"        ==cspace || "color"==cspace) && gs_abilities.havepng16m)   gsdev="png16m";
+  if(gsdev.empty()) {err="Colorspace "+cs.Value()+" is bad or unsupported"; goto fail;} // Incorrect value
  }
 
  // Antialiasing
  {
-  BaseM2String aa(input,"antialiasing","aa"),taa(input,"textantialiasing","taa"),gaa(input,"graphicsantialiasing","gaa");
-  if(aa.Exist()) aags=aats=aa(&suc);
-  if(taa.Exist()) aats=taa(&suc);
-  if(gaa.Exist()) aags=gaa(&suc);
-  if(!suc) goto fail; // Error
+  std::string aags=aa,aats=aa;
+  if(taa.Exist()) aats=taa;
+  if(gaa.Exist()) aags=gaa;
   tolower(aags); tolower(aats);
-  if("none"==aags || "no"==aags || "n"==aags) aag=1; if("none"==aats || "no"==aats || "n"==aats) aat=1;
-  if("small"==aags || "s"==aags) aag=2; if("small"==aats || "s"==aats) aat=2;
-  if("full"==aags || "f"==aags) aag=4; if("full"==aats || "f"==aats) aat=4;
-  if(0==aat || 0==aag) goto fail; // Incorrect value
+  if("none" ==aags || "no"==aags || "n"==aags) aag=1; if("none" ==aats || "no"==aats || "n"==aats) aat=1;
+  if("small"==aags || "s" ==aags             ) aag=2; if("small"==aats || "s" ==aats             ) aat=2;
+  if("full" ==aags || "f" ==aags             ) aag=4; if("full" ==aats || "f" ==aats             ) aat=4;
+  if(0==aat) {err="Incorrect value for text antialiasing: "+aats; goto fail;}
+  if(0==aag) {err="Incorrect value for graphics antialiasing: "+aags; goto fail;}
  }
 
  // Downscale
  if("pngmonod"==gsdev || "pnggray"==gsdev || "png16m"==gsdev)
  {
-  SearchParameterWDefO<double,DoubleDefaultVal<1>,false,PMin<1>,PMax<10>,PInt > ds(input,"downscale","dscale","ds");
-  dscale=static_cast<uint>(ds(&suc));
-  if(!suc) goto fail; // Error
-  r*=dscale;
+  dscale=static_cast<uint>(ds);
+  if(dscale<1 || dscale>10) {err="Downscale must be in interval from 1 to 10"; goto fail;}
+  res*=dscale;
  }
 
  // Go!
  {
   std::string* pdf=0;
   int ret;
-  if(!ispdf)
+  if(nullptr!=me)
   {
    pdf=new std::string;
-   ret=eps2pdf(*(map->pValue()),pdf,r,aat,aag);
-   if(0!=ret) { delete pdf; goto fail; } // Something wrong
+   ret=eps2pdf(*(me->pValue()),pdf,r,aat,aag);
+   if(0!=ret) {err="Can't convert EPS to PDF"; delete pdf; goto fail; } // Something wrong
   }
 
   {
    std::string* out=new std::string;
-   ret=GhostRun("-r"+ToString(r)+" -dTextAlphaBits="+ToString(aat)+" -dGraphicAlphaBits="+ToString(aag)+" -sDEVICE="+gsdev+((dscale>1)?(" -dDownScaleFactor="+ToString(dscale)):""),((0!=pdf)?*pdf:*(map->pValue())),0,0,out);
+   ret=GhostRun("-r"+ToString(res)+" -dTextAlphaBits="+ToString(aat)+" -dGraphicAlphaBits="+ToString(aag)+" -sDEVICE="+gsdev+((dscale>1)?(" -dDownScaleFactor="+ToString(dscale)):""),((0!=pdf)?*pdf:*(mp->pValue())),0,0,out);
    if(0!=pdf) delete pdf;
-   if(0!=ret) { delete out; goto fail; } // Something wrong
+   if(0!=ret) {err="Can't convert PDF to PNG"; delete out; goto fail; } // Something wrong
    return new ObjectGMTImage(out);
   }
  }
 
  fail:
- return 0;
+ return new ObjectError("EPS2PNG",err);
 }
 
 
@@ -410,104 +353,94 @@ antialiasing or aa - can be used to set graphics and text antialiasing simultane
 */
 const ObjectBase* GMT_Convert2JPG(const ObjectList* input)
 {
- if(!gs_abilities.havepdf) return 0; // No pdf support, so, no jpeg
- double r;
- bool suc=true;
- const GMTMap* map=0;
- std::string gsdev("");
- bool ispdf;
- uint aat=0,aag=0;
- std::string aats("full"),aags("full");
+ std::string gsdev,err;
+
+ ONPar<Base2PosD> r("resolution",300);
+ ONPar<Base2Pos> w("width"),h("height");
+ ONPar<Base2StringD> cs("c[olor][ ]space","color"),taa("t[ext]a[nti]aliasing","full"),gaa("g[raphics]a[nti]aliasing","full"),aa("a[nti]aliasing","full");
+ ONPar<Base2NonNegD> q("quality",75);
+ const ObjectGMTMap* me;
+ const ObjectGMTMapPDF* mp;
+ const GMTMap* m;
+ double res;
+ uint aat,aag;
  uint qual;
 
- // Map to convert
+ if(!gs_abilities.havepdf) {err="No PDF support in Ghostscript"; goto fail;} // No pdf support, so, no jpeg
+ // Search map
  {
-  for(ObjectList::IndexType i=0;i<input->Size();i++)
-  {
-   OBType<ObjectGMTMap> m(input->At(i));
-   OBType<ObjectGMTMapPDF> p(input->At(i));
-   if(m)
-   {
-    if(0!=map) goto fail; // Duplicate
-    map=m;
-    ispdf=false;
-   }
-   if(p)
-   {
-    if(0!=map) goto fail; // Duplicate
-    map=p;
-    ispdf=true;
-   }
-  }
-  if(0==map) goto fail; // Map not found
+  RNFPar<SearchGMTMap,ObjectGMTMap> mapeps("map");
+  RNFPar<SearchGMTMapPDF,ObjectGMTMap> mappdf("map");
+  ParseNamedParameters peps(input,mapeps);
+  ParseNamedParameters ppdf(input,mappdf);
+  if(!(peps || ppdf)) {err="Error parsing map parameter"; goto fail;}
+  me=mapeps; mp=mappdf;
+  if(nullptr==me && nullptr==mp) {err="Map parameter not specified"; goto fail;} // This must never happened
+  if(nullptr!=me) m=me; else m=mp;
+ }
+ // Parse other parameters
+ {
+  ParseNamedParameters params(input,r,q,w,h,cs,taa,gaa,aa);
+  if(!params) {err=params.Error(); goto fail;}
  }
 
  // Determine resolution
  {
-  SearchParameter<double,false,PMin<1> > res(input,"r","res","resolution");
-  BaseM2Double w(input,"width","w"), h(input,"height","h");
   // Check existence
-  if( ( res.Exist() && w.Exist() ) || ( res.Exist() && h.Exist() ) || ( w.Exist() && h.Exist() )) goto fail; // Only one parameter allowed
-  r=300; // Default value
-  if(res.Exist()) r=res(&suc);
-  if(w.Exist()) r=w(&suc)*72.0/(map->Bbrx()-map->Bblx());
-  if(h.Exist()) r=h(&suc)*72.0/(map->Bbry()-map->Bbly());
-  if(!suc) goto fail; // Error
+  if( ( r.Exist() && w.Exist() ) || ( r.Exist() && h.Exist() ) || ( w.Exist() && h.Exist() )) {err="Only one of resolution, width or height may be specified"; goto fail;} // Only one parameter allowed
+  if(r.Exist()) res=r;
+  if(w.Exist()) res=w*72.0/(m->Bbrx()-m->Bblx());
+  if(h.Exist()) res=h*72.0/(m->Bbry()-m->Bbly());
  }
 
  // Color model
  {
-  std::string cs;
-  BaseMD2String cspace(input,"8bit","colorspace","cspace","cs");
-  cs=cspace(&suc);
-  if(!suc) goto fail; // Error
-  tolower(cs);
-  if(("gray"==cs || "grey"==cs || "g"==cs) && gs_abilities.havejpeggray) gsdev="jpeggray";
-  if(("full"==cs || "8bit"==cs || "color"==cs) && gs_abilities.havejpeg) gsdev="jpeg";
-  if(""==gsdev) goto fail; // Incorrect value
+  std::string cspace=cs;
+  tolower(cspace);
+  if(("gray"==cspace || "grey"==cspace || "g"    ==cspace) && gs_abilities.havejpeggray) gsdev="jpeggray";
+  if(("full"==cspace || "8bit"==cspace || "color"==cspace) && gs_abilities.havejpeg)     gsdev="jpeg";
+  if(gsdev.empty()) {err="Colorspace "+cs.Value()+" is bad or unsupported"; goto fail;} // Incorrect value
  }
 
  // Antialiasing
  {
-  BaseM2String aa(input,"antialiasing","aa"),taa(input,"textantialiasing","taa"),gaa(input,"graphicsantialiasing","gaa");
-  if(aa.Exist()) aags=aats=aa(&suc);
-  if(taa.Exist()) aats=taa(&suc);
-  if(gaa.Exist()) aags=gaa(&suc);
-  if(!suc) goto fail; // Error
+  std::string aags=aa,aats=aa;
+  if(taa.Exist()) aats=taa;
+  if(gaa.Exist()) aags=gaa;
   tolower(aags); tolower(aats);
-  if("none"==aags || "no"==aags || "n"==aags) aag=1; if("none"==aats || "no"==aats || "n"==aats) aat=1;
-  if("small"==aags || "s"==aags) aag=2; if("small"==aats || "s"==aats) aat=2;
-  if("full"==aags || "f"==aags) aag=4; if("full"==aats || "f"==aats) aat=4;
-  if(0==aat || 0==aag) goto fail; // Incorrect value
+  if("none" ==aags || "no"==aags || "n"==aags) aag=1; if("none" ==aats || "no"==aats || "n"==aats) aat=1;
+  if("small"==aags || "s" ==aags             ) aag=2; if("small"==aats || "s" ==aats             ) aat=2;
+  if("full" ==aags || "f" ==aags             ) aag=4; if("full" ==aats || "f" ==aats             ) aat=4;
+  if(0==aat) {err="Incorrect value for text antialiasing: "+aats; goto fail;}
+  if(0==aag) {err="Incorrect value for graphics antialiasing: "+aags; goto fail;}
  }
 
  // Quality
  {
-  SearchParameterWDefO<double,DoubleDefaultVal<75>,false,PMin<0>,PMax<100>,PInt > q(input,"quality","qual","q");
-  qual=static_cast<uint>(q(&suc));
-  if(!suc) goto fail; // Error
+  qual=static_cast<uint>(q);
+  if(q>100) {err="JPEG quality must not exceed 100"; goto fail;} // Error
  }
 
  // Go!
  {
   std::string* pdf=0;
   int ret;
-  if(!ispdf)
+  if(nullptr!=me)
   {
    pdf=new std::string;
-   ret=eps2pdf(*(map->pValue()),pdf,r,aat,aag);
-   if(0!=ret) { delete pdf; goto fail; } // Something wrong
+   ret=eps2pdf(*(me->pValue()),pdf,r,aat,aag);
+   if(0!=ret) {err="Can't convert EPS to PDF"; delete pdf; goto fail; } // Something wrong
   }
 
   {
    std::string* out=new std::string;
-   ret=GhostRun("-r"+ToString(r)+" -dTextAlphaBits="+ToString(aat)+" -dGraphicAlphaBits="+ToString(aag)+" -sDEVICE="+gsdev+" -dJPEGQ="+ToString(qual),((0!=pdf)?*pdf:*(map->pValue())),0,0,out);
+   ret=GhostRun("-r"+ToString(res)+" -dTextAlphaBits="+ToString(aat)+" -dGraphicAlphaBits="+ToString(aag)+" -sDEVICE="+gsdev+" -dJPEGQ="+ToString(qual),((0!=pdf)?*pdf:*(mp->pValue())),0,0,out);
    if(0!=pdf) delete pdf;
-   if(0!=ret) { delete out; goto fail; } // Something wrong
+   if(0!=ret) {err="Can't convert PDF to JPEG"; delete out; goto fail; } // Something wrong
    return new ObjectGMTImage(out);
   }
  }
 
  fail:
- return 0;
+ return new ObjectError("EPS2JPEG",err);
 }
diff --git a/modules/gmt/modgmt_map.h b/modules/gmt/modgmt_map.h
index cad08c4..57e7f91 100644
--- a/modules/gmt/modgmt_map.h
+++ b/modules/gmt/modgmt_map.h
@@ -72,12 +72,29 @@ class ObjectGMTImage: public GMTBlob
  std::string Type() const override {return "GMTImage";}
 };
 
-// Policy for get integer value
-class PInt
+// Convertor to search object
+template<class Object>
+class SearchObject
 {
  public:
- double operator()(double v, bool* suc) const {if(v!=floor(v)) *suc=false; return v;}
+ using ValueType=const Object*;
+ template<class... Args>
+ ValueType Convert(const ObjectBase* ob, bool* res, std::string& err, Args... args)
+ {
+  OBType<Object> gp(ob);
+  switch(gp.Error())
+  {
+   case(OBTypeErr::OK): return gp;
+   case(OBTypeErr::NULLPTR): {err="Can't convert zero ObjectBase pointer to something meaningfull"; break;}
+   case(OBTypeErr::TYPEMISMATCH): {err=ob->Type()+" is not correct: type mismatch"; break;}
+  }
+  *res=false;
+  return nullptr;
+ }
 };
+// Convertor to search GMTMap objects
+using SearchGMTMap=SearchObject<ObjectGMTMap>;
+using SearchGMTMapPDF=SearchObject<ObjectGMTMapPDF>;
 
 // Creating eps map from set of layers
 const ObjectBase* GMT_Map(const ObjectList* input);