diff --git a/src/parser/grammatical.y b/src/parser/grammatical.y
index 0c933bf..fbad0c3 100644
--- a/src/parser/grammatical.y
+++ b/src/parser/grammatical.y
@@ -11,6 +11,9 @@
 %locations
 //%no-lines
 
+// Get name of initial parsed file
+%initial-action {@$.filename=confget_extra(scanner)->state.curdir+confget_extra(scanner)->state.filename;}
+
 %{
 #include <inttypes.h>
 #include <algorithm>
@@ -18,17 +21,25 @@
 #include "../debug.h"
 #include "../object.h"
 #include "../globals.h"
+// We can't include lexical.h before grammatical.h, because of strange errors, but grammatical.h only needs definition of yyscan_t
 #ifndef YY_TYPEDEF_YY_SCANNER_T
 #define YY_TYPEDEF_YY_SCANNER_T
 typedef void* yyscan_t;
 #endif
-#include "yyloc.h"
+
 #include "grammatical.h"
-inline void conferror(YYLTYPE *locp, yyscan_t sc, const char * str)
+#include "lexical.h"
+
+inline void conferror(const YYLTYPE* locp, yyscan_t sc, const char* str)
 {
- COUT(ERROR)<<std::endl<<" Grammatical parser: "<<str<<std::endl;
+ COUT(ERROR)<<std::endl<<" Grammatical parser: "<<str<<std::endl<<"  in file "<<locp->filename;
+ if(locp->first_line==locp->last_line) COUT(ERROR)<<" at line "<<locp->last_line<<", from position "<<locp->first_column<<" to "<<locp->last_column<<std::endl;
+ else COUT(ERROR)<<" from line "<<locp->first_line<<", position "<<locp->first_column<<" to line "<<locp->last_line<<", position "<<locp->last_column<<std::endl;
+}
+inline void conferror(const YYLTYPE& locp, yyscan_t sc, const std::string& str)
+{
+ conferror(&locp,sc,str.c_str());
 }
-#include "lexical.h"
 %}
 
 %union
@@ -84,7 +95,7 @@ line:
                                                  else if(*$1=="print") G_toprint.push_back(ol);
                                                  else
                                                  {
-                                                  COUT(ERROR)<<std::endl<<"Unknown statement "<<(*$1)<<std::endl;
+                                                  conferror(@1,scanner,"unknown statement "+(*$1));
                                                   delete ol;
                                                   delete $1;
                                                   YYABORT;
@@ -97,7 +108,7 @@ line:
                                                  else if(*$1=="print") G_toprint.push_back(ol);
                                                  else
                                                  {
-                                                  COUT(ERROR)<<std::endl<<"Unknown statement "<<(*$1)<<std::endl;
+                                                  conferror(@1,scanner,"unknown statement "+(*$1));
                                                   delete ol;
                                                   delete $1;
                                                   YYABORT;
diff --git a/src/parser/lexical.l b/src/parser/lexical.l
index b601a67..67b1fdf 100644
--- a/src/parser/lexical.l
+++ b/src/parser/lexical.l
@@ -15,24 +15,29 @@
 %x INCLUDE
 
 %{
-#if __cplusplus > 199711L
-#define register      // Deprecated in C++11.
-#endif  // #if __cplusplus > 199711L
-#include <stdlib.h>
 #include "../debug.h"
-#include "../object.h"
 #include "parser.h"
+// flex use register keyword, but it deprecated in C++11.
+#define register
+// Flex always think what bison types prefixed as YY, so we mast define right macroses
+#define YYSTYPE CONFSTYPE
+#define YYLTYPE CONFLTYPE
+// Some declarations in grammatical.h use ObjectBase
+class ObjectBase;
 #include "grammatical.h"
 // Get rid of warning on unused function
 #define YY_NO_INPUT
-// definitions for bison-bridge
-#define YYSTYPE CONFSTYPE
-#define YYLTYPE CONFLTYPE
-std::string str;
+// Termination (mostly. in case of errors)
 #define yyterminate(ret) { while(YY_CURRENT_BUFFER) yypop_buffer_state(yyscanner); str.erase(); yyextra->retcode=-(ret); return (ret); }
+// Abnormal termination with description of error
 #define yyerrormessage(message,ret) {COUT(ERROR)<<std::endl<<" Lexical error in file "<<yyextra->state.curdir<<yyextra->state.filename<<" at line "<<yyextra->state.curline<<": "<<(message)<<std::endl; yyterminate(ret);}
+// Trace position
 #define yynextline {yyextra->state.curline++; yyextra->state.curpos=0; yyextra->state.curoffset++;}
 #define yynextsym {yyextra->state.curpos+=yyleng; yyextra->state.curoffset+=yyleng;}
+// and set bison location accordingly
+#define setyyllocp {yylloc_param->first_line=yylloc_param->last_line=yyextra->state.curline; yylloc_param->first_column=yyextra->state.curpos; yylloc_param->last_column=yylloc_param->first_column+yyleng;}
+
+std::string str;
 %}
 
 %%
@@ -62,34 +67,35 @@ std::string str;
                                                  yyextra->ParsePath(str);
                                                  yyextra->state.curline=1;
                                                  yyextra->state.curpos=yyextra->state.curoffset=0;
+                                                 yylloc_param->filename=yyextra->state.curdir+yyextra->state.filename;
 
                                                  yypush_buffer_state(yy_create_buffer(fd,YY_BUF_SIZE,yyscanner),yyscanner);
                                                  // Get rid of warning on unused function
                                                  if(__builtin_expect(yy_top_state(yyscanner)==PSTRING,0)) yyerrormessage("misterious error",-1);
                                                  yy_pop_state(yyscanner);
                                                 }
-[a-zA-Z][a-zA-Z0-9_]*                           COUT(MOREDEBUG)<<"NAME("<<yytext<<")"; BEGIN(PARSE); yylval_param->str=new std::string(yytext); yynextsym; return NAME;
-<PARSE>[+\-*/^]                                 COUT(MOREDEBUG)<<" OPERATION("<<yytext<<")"; return yytext[0]; yynextsym;
-<PARSE>[0-9]+   				COUT(MOREDEBUG)<<" INTEGER("<<yytext<<")"; yylval_param->i=atoll(yytext); yynextsym; return INTEGER;
-<PARSE>[0-9]+(\.[0-9]*)?([eE][+-][0-9]+)?	COUT(MOREDEBUG)<<" REAL("<<yytext<<")"; yylval_param->r=atof(yytext); yynextsym; return REAL;
-<PARSE>[TF]                                     COUT(MOREDEBUG)<<" BOOL("<<yytext<<")"; yylval_param->b=(yytext[0]=='T')?true:false; yynextsym; return BOOL;
-<PARSE>\(					COUT(MOREDEBUG)<<" OBRACE()"; yynextsym; return OBRACE;
-<PARSE>\)					COUT(MOREDEBUG)<<" CBRACE()"; yynextsym; return CBRACE;
-<PARSE>\;					COUT(MOREDEBUG)<<" ENDL()"<<std::endl; BEGIN(0); yynextsym; return ENDL;
-<PARSE>=					COUT(MOREDEBUG)<<" ASSIGN()"; yynextsym; return ASSIGN;
-<PARSE>,                                        COUT(MOREDEBUG)<<" DELIM()"; yynextsym; return DELIM;
-<PARSE>[a-zA-Z][a-zA-Z0-9_]*		        COUT(MOREDEBUG)<<" IDENTIFIER("<<yytext<<")"; yylval_param->str=new std::string(yytext); yynextsym; return IDENTIFIER;
-<PARSE>\.                                       COUT(MOREDEBUG)<<" DOT()"; yynextsym; return yytext[0];
+[a-zA-Z][a-zA-Z0-9_]*                           COUT(MOREDEBUG)<<"NAME("<<yytext<<")"; BEGIN(PARSE); yylval_param->str=new std::string(yytext); setyyllocp; yynextsym; return NAME;
+<PARSE>[+\-*/^]                                 COUT(MOREDEBUG)<<" OPERATION("<<yytext<<")"; setyyllocp; yynextsym; return yytext[0];
+<PARSE>[0-9]+   				COUT(MOREDEBUG)<<" INTEGER("<<yytext<<")"; yylval_param->i=atoll(yytext); setyyllocp; yynextsym; return INTEGER;
+<PARSE>[0-9]+(\.[0-9]*)?([eE][+-][0-9]+)?	COUT(MOREDEBUG)<<" REAL("<<yytext<<")"; yylval_param->r=atof(yytext); setyyllocp; yynextsym; return REAL;
+<PARSE>[TF]                                     COUT(MOREDEBUG)<<" BOOL("<<yytext<<")"; yylval_param->b=(yytext[0]=='T')?true:false; setyyllocp; yynextsym; return BOOL;
+<PARSE>\(					COUT(MOREDEBUG)<<" OBRACE()"; setyyllocp; yynextsym; return OBRACE;
+<PARSE>\)					COUT(MOREDEBUG)<<" CBRACE()"; setyyllocp; yynextsym; return CBRACE;
+<PARSE>\;					COUT(MOREDEBUG)<<" ENDL()"<<std::endl; BEGIN(0); setyyllocp; yynextsym; return ENDL;
+<PARSE>=					COUT(MOREDEBUG)<<" ASSIGN()"; setyyllocp; yynextsym; return ASSIGN;
+<PARSE>,                                        COUT(MOREDEBUG)<<" DELIM()"; setyyllocp; yynextsym; return DELIM;
+<PARSE>[a-zA-Z][a-zA-Z0-9_]*		        COUT(MOREDEBUG)<<" IDENTIFIER("<<yytext<<")"; yylval_param->str=new std::string(yytext); setyyllocp; yynextsym; return IDENTIFIER;
+<PARSE>\.                                       COUT(MOREDEBUG)<<" DOT()"; setyyllocp; yynextsym; return yytext[0];
 <PARSE,INITIAL>[ \t]+                           yynextsym;
 <PARSE,INITIAL>\n                               yynextline;
 <PARSE,INITIAL>\#.*                             yynextsym;
-<PARSE>\"				        BEGIN(PSTRING); str.erase(); yynextsym;
+<PARSE>\"				        BEGIN(PSTRING); str.erase(); yyextra->states.push(yyextra->state); yynextsym;
 <PARSE,INITIAL>.                                yyerrormessage(std::string("unknown symbol ")+yytext+" at position "+std::to_string(yyextra->state.curpos),-1);
 <PSTRING,INCLUDE>\\\\				str+='\\'; yynextsym;
 <PSTRING,INCLUDE>\\\"	        		str+='\"'; yynextsym;
 <PSTRING>\n                                     str+=yytext[0]; yynextline;
-<PSTRING>\"					BEGIN(PARSE); COUT(MOREDEBUG)<<" STRING("<<str<<")"; yylval_param->str=new std::string(str); yynextsym;  return STRING;
+<PSTRING>\"					BEGIN(PARSE); COUT(MOREDEBUG)<<" STRING("<<str<<")"; yylval_param->str=new std::string(str); {struct lexical_state prstate=yyextra->states.top(); yyextra->states.pop(); yylloc_param->first_line=prstate.curline; yylloc_param->last_line=yyextra->state.curline; yylloc_param->first_column=prstate.curpos; yylloc_param->last_column=yyextra->state.curpos+yyleng;}; yynextsym; return STRING;
 <PSTRING,INCLUDE>.				str+=yytext[0]; yynextsym;
-<PSTRING,INCLUDE><<EOF>>			yyerrormessage("unclosed quote",-1);
-<<EOF>>						yypop_buffer_state(yyscanner); if(YY_CURRENT_BUFFER) {yyextra->state=yyextra->states.top(); yyextra->states.pop(); fclose(yyextra->fds.top()); yyextra->fds.pop();} else yyterminate(0);
+<PSTRING,INCLUDE><<EOF>>			yyextra->states.pop(); yyerrormessage("unclosed quote",-1);
+<<EOF>>						yypop_buffer_state(yyscanner); if(YY_CURRENT_BUFFER) {yyextra->state=yyextra->states.top(); yyextra->states.pop(); fclose(yyextra->fds.top()); yyextra->fds.pop(); yylloc_param->filename=yyextra->state.curdir+yyextra->state.filename;} else yyterminate(0);
 %%
diff --git a/src/parser/parser.h b/src/parser/parser.h
index dd745c5..720fab0 100644
--- a/src/parser/parser.h
+++ b/src/parser/parser.h
@@ -4,6 +4,7 @@
 #include <stack>
 #include <stdio.h>
 
+// State of lexical parser (filename and position in file)
 struct lexical_state
 {
  std::string filename,curdir;
@@ -11,6 +12,7 @@ struct lexical_state
  unsigned int curline,curpos,curoffset;
 };
 
+// Container for "static" parameters of lexical parser
 struct lexical_extra
 {
  struct lexical_state state;
@@ -31,4 +33,19 @@ struct lexical_extra
  }
 };
 
+// Bison location
+struct grammatic_location
+{
+  int first_line;
+  int first_column;
+  int last_line;
+  int last_column;
+  std::string filename;
+};
+
+#if !defined CONFLTYPE && !defined CONFLTYPE_IS_DECLARED
+typedef struct grammatic_location CONFLTYPE;
+#define CONFLTYPE_IS_DECLARED 1
+#endif
+
 #endif
diff --git a/src/parser/yyloc.h b/src/parser/yyloc.h
deleted file mode 100644
index fc61489..0000000
--- a/src/parser/yyloc.h
+++ /dev/null
@@ -1,19 +0,0 @@
-#ifndef PARSER_YYLOC_H
-#define PARSER_YYLOC_H
-#include <string.h>
-
-#if ! defined YYLTYPE && ! defined YYLTYPE_IS_DECLARED
-typedef struct YYLTYPE
-{
-  int first_line;
-  int first_column;
-  int last_line;
-  int last_column;
-  std::string filename;
-  std::string token_type;
-  std::string token_value;
-} YYLTYPE;
-#define YYLTYPE_IS_DECLARED 1
-#endif
-
-#endif