diff --git a/DtsodParser/DtsodV24_deserialize.c b/DtsodParser/DtsodV24_deserialize.c
index adedb24..8018192 100644
--- a/DtsodParser/DtsodV24_deserialize.c
+++ b/DtsodParser/DtsodV24_deserialize.c
@@ -171,7 +171,6 @@ Unitype __ParseValue(DeserializeSharedData* shared, string str){
                             sprintf(err,"can't parse to int: <%s>",_c);
                             throw(err);
                         }
-                            
                         free(_c);
                         return Uni(Int64,li);
                     }
diff --git a/Makefile b/Makefile
index dfc7810..3bedacc 100644
--- a/Makefile
+++ b/Makefile
@@ -3,7 +3,7 @@ TESTS=$(wildcard tests/*c) $(wildcard tests/**/*.c)
 OUTDIR=bin
 CMP=gcc
 
-all: clear_c clear_bin build_test build_lib
+all: clear_c clear_bin build_test
 
 clear_c:
 	clear
diff --git a/base/base.h b/base/base.h
index b9001c5..906b6ed 100644
--- a/base/base.h
+++ b/base/base.h
@@ -10,23 +10,26 @@ extern "C" {
 #include "mystr.h"
 
 // executes codeblock and prints execution time
-/*#define optime(opname,repeats,codeblock) ({\
-    struct timespec start, stop;\
-    clock_gettime(CLOCK_REALTIME, &start);\
-    for(uint64 ___OPREP=0;___OPREP<repeats;___OPREP++)\
-        (codeblock);\
-    clock_gettime(CLOCK_REALTIME, &stop);\
-    double t=(double)(stop.tv_sec-start.tv_sec+(double)(stop.tv_nsec-start.tv_nsec)/1000000000)/repeats;\
-    printf("\e[93moperation \e[94m%s\e[93m lasted \e[94m%lf \e[93mseconds\n",opname,t);\
-})*/
-#define optime(opname,repeats,codeblock) ({\
-    clock_t start=clock();\
-    for(uint64 ___OPREP=0;___OPREP<repeats;___OPREP++)\
-        (codeblock);\
-    clock_t stop=clock();\
-    double t=(double)(stop-start)/CLOCKS_PER_SEC/repeats;\
-    printf("\e[93moperation \e[94m%s\e[93m lasted \e[94m%lf \e[93mseconds\n",opname,t);\
-})
+#ifdef CLOCK_REALTIME //non-standard high-precision clock
+    #define optime(opname,repeats,codeblock) ({\
+        struct timespec start, stop;\
+        clock_gettime(CLOCK_REALTIME, &start);\
+        for(uint64 ___OPREP=0;___OPREP<repeats;___OPREP++)\
+            (codeblock);\
+        clock_gettime(CLOCK_REALTIME, &stop);\
+        double t=(double)(stop.tv_sec-start.tv_sec+(double)(stop.tv_nsec-start.tv_nsec)/1000000000)/repeats;\
+        printf("\e[93moperation \e[94m%s\e[93m lasted \e[94m%lf \e[93mseconds\n",opname,t);\
+    })
+#else //
+    #define optime(opname,repeats,codeblock) ({\
+        clock_t start=clock();\
+        for(uint64 ___OPREP=0;___OPREP<repeats;___OPREP++)\
+            (codeblock);\
+        clock_t stop=clock();\
+        double t=(double)(stop-start)/CLOCKS_PER_SEC/repeats;\
+        printf("\e[93moperation \e[94m%s\e[93m lasted \e[94m%lf \e[93mseconds\n",opname,t);\
+    })
+#endif
 
 #if __cplusplus
 }
diff --git a/base/errors.c b/base/errors.c
index 13f6528..a1ef3c1 100644
--- a/base/errors.c
+++ b/base/errors.c
@@ -1,7 +1,8 @@
 #include "std.h"
 #include "errors.h"
+#include "mystr.h"
 
-const char* errname(err_t err){
+char* errname(err_t err){
     switch(err){
         case SUCCESS: return "SUCCESS";
         case ERR_MAXLENGTH: return "ERR_MAXLENGTH";
@@ -14,14 +15,29 @@ const char* errname(err_t err){
     }
 }
 
-void _throwint(int err, const char* srcfile, int line, const char* funcname){
-    if(err){ // SUCCESS=0 is not an error
-        printf("\e[91m[%s:%d %s] throwed error: %s\e[0m\n",srcfile,line,funcname,errname(err));
-        exit(err); 
-    }
-    else printf("\e[93m[%s:%d %s] throwed SUCCESS as an error",srcfile,line,funcname);
+#define ERRMSG_MAXLENGTH 1024
+
+char* __genErrMsg(const char* errmsg, const char* srcfile, int line, const char* funcname){
+    char* rezult=malloc(ERRMSG_MAXLENGTH);
+    sprintf(rezult,"[%s:%d] %s() throwed error: %s",srcfile,line,funcname,errmsg);
+    return rezult;
 }
-void _throwstr(const char* errmesg, const char* srcfile, int line, const char* funcname){
-    printf("\e[91m[%s:%d %s] throwed error: %s\e[0m\n",srcfile,line,funcname,errmesg);
-    exit(255); 
-}
\ No newline at end of file
+
+char* __extendErrMsg(const char* errmsg, const char* srcfile, int line, const char* funcname){
+    char* rezult=malloc(cptr_length(errmsg)+ERRMSG_MAXLENGTH);
+    sprintf(rezult,"%s\n \\___[%s:%d] %s()",errmsg,srcfile,line,funcname);
+    free(errmsg);
+    return rezult;
+}
+
+void Maybe_free(Maybe e){
+    free(e.errmsg);
+    Unitype_free(e.value);
+}
+void printMaybe(Maybe e){
+    if(e.errmsg) printf("%s\n",e.errmsg);
+    else printuni(e.value);
+}
+
+char* __doNothing(char* a) {return a;}
+char* __unknownErr() {return "UNKNOWN ERROR";}
\ No newline at end of file
diff --git a/base/errors.h b/base/errors.h
index 8a6c813..708f801 100644
--- a/base/errors.h
+++ b/base/errors.h
@@ -4,20 +4,51 @@
 extern "C" {
 #endif
 
+#include "std.h"
+#include "types.h"
+
 typedef enum err_t {
     SUCCESS, //not an error 
     ERR_MAXLENGTH, ERR_WRONGTYPE, ERR_WRONGINDEX, ERR_NOTIMPLEMENTED, ERR_NULLPTR, ERR_ENDOFSTR
 } err_t;
 
-const char* errname(err_t err);
+char* errname(err_t err);
 
-void _throwint(int err, const char* srcfile, int line, const char* funcname) ;
-void _throwstr(const char* errmesg, const char* srcfile, int line, const char* funcname);
-#pragma GCC diagnostic ignored "-Wint-conversion"
-#define throw(E) \
-    CHOOSE(IFTYPE(E,int), _throwint(E,__FILE__,__LINE__,__func__), \
-    CHOOSE(IFTYPE(E,char[]), _throwstr(E,__FILE__,__LINE__,__func__), \
-    printf("\e[31m[%s:%d/%s] UNKNOWN ERROR\n",__FILE__,__LINE__,__func__)))
+char* __genErrMsg(const char* errmsg, const char* srcfile, int line, const char* funcname);
+char* __extendErrMsg(const char* errmsg, const char* srcfile, int line, const char* funcname);
+
+typedef struct Maybe{
+    Unitype value;
+    char* errmsg;
+} Maybe;
+static const Maybe MaybeNull={.value.type=Null, .value.VoidPtr=NULL,.errmsg=NULL};
+
+void Maybe_free(Maybe e);
+void printMaybe(Maybe e);
+
+#define throwNext(_funcCall, _rezult) Maybe _rezult=_funcCall; if(_rezult.errmsg){\
+        _rezult.errmsg=__extendErrMsg(_rezult.errmsg, __FILE__,__LINE__,__func__);\
+        return _rezult;\
+    }else 
+
+#define SUCCESS(REZLT) (Maybe){.errmsg=NULL, .value=REZLT}
+
+#define __RETURN_EXCEPTION(ERRMSG) return (Maybe){.errmsg=ERRMSG, .value=UniNull}
+
+#define __EXIT(ERRMSG) ({ printf("\e[91m%s\e[0m \n", ERRMSG); exit(128); })
+
+char* __doNothing(char* a);
+char* __unknownErr( );
+
+#define __stringify_err(E) _Generic(\
+    (E),\
+    char*: __doNothing,\
+    int: errname,\
+    default: __unknownErr\
+)(E)
+
+#define throw(E) __EXIT(((char*)__genErrMsg((__stringify_err(E)), __FILE__,__LINE__,__func__)))
+#define safethrow(E) __RETURN_EXCEPTION(((char*)__genErrMsg((__stringify_err(E)), __FILE__,__LINE__,__func__)))
 
 #if __cplusplus
 }
diff --git a/base/mystr.c b/base/mystr.c
index ad498a7..5503b46 100644
--- a/base/mystr.c
+++ b/base/mystr.c
@@ -37,8 +37,8 @@ char* char_multiply(char c, uint32 n){
 
 //copies str content to new char pointer value (adding '\0' at the end)
 char* string_cpToCptr(string str){
-    char* cptr=malloc(str.length*sizeof(char)+1);
     if(str.length==0) return NULL;
+    char* cptr=malloc(str.length*sizeof(char)+1);
     cptr[str.length]=0;
     while(str.length-->0)
         cptr[str.length]=str.ptr[str.length];
@@ -69,6 +69,7 @@ bool string_compare(string str0, string str1){
 
 //creates new string which is reversed variant of <s>
 string string_reverse(string s){
+    if(s.length==0) return s;
     string r={malloc(s.length), s.length};
     for(uint32 i=0; i<s.length; i++)
         r.ptr[i]=s.ptr[s.length-i-1];
diff --git a/base/std.h b/base/std.h
index dc5641f..a2415d2 100644
--- a/base/std.h
+++ b/base/std.h
@@ -10,6 +10,7 @@ extern "C" {
 #include <stdbool.h>
 #include <locale.h>
 #include <time.h>
+#include <setjmp.h>
 
 #define CHOOSE(B, Y, N) __builtin_choose_expr(B, Y, N)
 
diff --git a/base/types.c b/base/types.c
index 8aa92fe..95c2dd7 100644
--- a/base/types.c
+++ b/base/types.c
@@ -115,16 +115,22 @@ void Unitype_free(Unitype u){
     }
 }
 
-
-void printuni(Unitype v){
+void sprintuni(char* buf,Unitype v){
     switch (v.type) {
-        case Null: printf("{Null}");break;
-        case Float64: printf("{%s : %lf}",my_type_name(v.type),v.Float64);break;
-        case Char: printf("{%s : '%c'}",my_type_name(v.type),v.Char);break;
+        case Null: sprintf(buf, "{Null}");break;
+        case Float64: sprintf(buf, "{%s : %lf}",my_type_name(v.type),v.Float64);break;
+        case Char: sprintf(buf, "{%s : '%c'}",my_type_name(v.type),v.Char);break;
         case Bool:
-        case UInt64: printf("{%s : %lu}",my_type_name(v.type),v.UInt64);break;
-        case Int64: printf("{%s : %ld}",my_type_name(v.type),v.Int64);break;
-        case CharPtr: printf("{%s : \"%s\"}",my_type_name(v.type),(char*)v.VoidPtr);break;
-        default: printf("{%s : %p}",my_type_name(v.type),v.VoidPtr);break;
+        case UInt64: sprintf(buf, "{%s : %lu}",my_type_name(v.type),v.UInt64);break;
+        case Int64: sprintf(buf, "{%s : %ld}",my_type_name(v.type),v.Int64);break;
+        case CharPtr: sprintf(buf, "{%s : \"%s\"}",my_type_name(v.type),(char*)v.VoidPtr);break;
+        default: sprintf(buf, "{%s : %p}",my_type_name(v.type),v.VoidPtr);break;
     }
 }
+
+void printuni(Unitype v){
+    char* s=malloc(64);
+    sprintuni(s,v);
+    fputs(s, stdout);
+    free(s);
+}
\ No newline at end of file
diff --git a/base/types.h b/base/types.h
index af08c82..08d2461 100644
--- a/base/types.h
+++ b/base/types.h
@@ -51,6 +51,7 @@ static const Unitype UniFalse={.Bool=false,.type=Bool};
 //frees VoidPtr value or does nothing if type isn't pointer
 void Unitype_free(Unitype u);
 void printuni(Unitype v);
+void sprintuni(char* s, Unitype v);
 
 #if __cplusplus
 }
diff --git a/kerep.vcxproj b/kerep.vcxproj
index cfcdc93..5ed9303 100644
--- a/kerep.vcxproj
+++ b/kerep.vcxproj
@@ -75,27 +75,27 @@
   </ImportGroup>
   <PropertyGroup Label="UserMacros" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
-    <OutDir>bin-$(Platform)\$(Configuration)\</OutDir>
-    <IntDir>obj-$(Platform)\$(Configuration)\</IntDir>
+    <OutDir>bin\$(Configuration)-$(Platform)\</OutDir>
+    <IntDir>obj\$(Configuration)-$(Platform)\</IntDir>
     <RunCodeAnalysis>true</RunCodeAnalysis>
     <ManagedAssembly>false</ManagedAssembly>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
-    <OutDir>bin-$(Platform)\$(Configuration)\</OutDir>
-    <IntDir>obj-$(Platform)\$(Configuration)\</IntDir>
+    <OutDir>bin\$(Configuration)-$(Platform)\</OutDir>
+    <IntDir>obj\$(Configuration)-$(Platform)\</IntDir>
     <RunCodeAnalysis>true</RunCodeAnalysis>
     <ManagedAssembly>false</ManagedAssembly>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">
     <RunCodeAnalysis>true</RunCodeAnalysis>
-    <OutDir>bin-$(Platform)\$(Configuration)\</OutDir>
-    <IntDir>obj-$(Platform)\$(Configuration)\</IntDir>
+    <OutDir>bin\$(Configuration)-$(Platform)\</OutDir>
+    <IntDir>obj\$(Configuration)-$(Platform)\</IntDir>
     <ManagedAssembly>false</ManagedAssembly>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|x64'">
     <RunCodeAnalysis>true</RunCodeAnalysis>
-    <OutDir>bin-$(Platform)\$(Configuration)\</OutDir>
-    <IntDir>obj-$(Platform)\$(Configuration)\</IntDir>
+    <OutDir>bin\$(Configuration)-$(Platform)\</OutDir>
+    <IntDir>obj\$(Configuration)-$(Platform)\</IntDir>
     <ManagedAssembly>false</ManagedAssembly>
   </PropertyGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
@@ -220,6 +220,8 @@
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="Autoarr\Autoarr.c" />
+    <ClCompile Include="Autoarr\Autoarr_KVPair_exported.c" />
+    <ClCompile Include="Autoarr\Autoarr_Unitype_exported.c" />
     <ClCompile Include="Autoarr\StringBuilder.c" />
     <ClCompile Include="base\errors.c" />
     <ClCompile Include="base\mystr.c" />
@@ -237,6 +239,7 @@
     <ClCompile Include="tests\test_dtsod.c" />
     <ClCompile Include="tests\test_hashtable.c" />
     <ClCompile Include="tests\test_marshalling.c" />
+    <ClCompile Include="tests\test_safethrow.c" />
     <ClCompile Include="tests\test_searchtree.c" />
     <ClCompile Include="tests\test_string.c" />
   </ItemGroup>
diff --git a/kerep.vcxproj.filters b/kerep.vcxproj.filters
index a4008fb..802eb88 100644
--- a/kerep.vcxproj.filters
+++ b/kerep.vcxproj.filters
@@ -125,5 +125,14 @@
     <ClCompile Include="DtsodParser\DtsodV24_exported.c">
       <Filter>Исходные файлы</Filter>
     </ClCompile>
+    <ClCompile Include="Autoarr\Autoarr_KVPair_exported.c">
+      <Filter>Исходные файлы</Filter>
+    </ClCompile>
+    <ClCompile Include="Autoarr\Autoarr_Unitype_exported.c">
+      <Filter>Исходные файлы</Filter>
+    </ClCompile>
+    <ClCompile Include="tests\test_safethrow.c">
+      <Filter>Исходные файлы</Filter>
+    </ClCompile>
   </ItemGroup>
 </Project>
\ No newline at end of file
diff --git a/tests/main.c b/tests/main.c
index 47445cc..a91c53e 100644
--- a/tests/main.c
+++ b/tests/main.c
@@ -6,6 +6,7 @@ void test_all(){
     test_hashtable();
     test_string();
     test_dtsod();
+    test_safethrow();
     printf("\e[96m---------------------------------------\e[0m\n");
 }
 
diff --git a/tests/test_safethrow.c b/tests/test_safethrow.c
new file mode 100644
index 0000000..17dff57
--- /dev/null
+++ b/tests/test_safethrow.c
@@ -0,0 +1,43 @@
+#include "tests.h"
+
+Maybe dont_throw(){
+    return SUCCESS(Uni(UInt64, 9/2));
+}
+
+Maybe throw_error(){
+    safethrow("test exception");
+}
+
+Maybe throw_errcode(){
+    safethrow(ERR_NULLPTR);
+}
+
+Maybe test_maybe(){
+    printf("\e[94mdont_throw returns \e[92m");
+    throwNext(dont_throw(),rez0)
+        printMaybe(rez0);
+    printf("\n");
+    throwNext(throw_error(),rez1)
+        printMaybe(rez1);
+    throw("test_maybe failed");
+    return MaybeNull;
+}
+
+
+Maybe c(){ throwNext(throw_errcode(),_) return MaybeNull; }
+Maybe b(){ throwNext(c(),_) return MaybeNull; }
+Maybe a(){ throwNext(b(),_) return MaybeNull; }
+
+void test_safethrow(){
+    printf("\e[96m-----------[test_safethrow]-----------\n");
+    optime("test_safethrow", 1, ({
+        Maybe e=test_maybe();
+        printf("\e[94mthrow_error:\n\e[92m");
+        printMaybe(e);
+        Maybe_free(e);
+        printf("\e[94mthrow_errcode:\n\e[92m");
+        e=a();
+        printMaybe(e);
+        Maybe_free(e);
+    }));
+}
diff --git a/tests/test_string.c b/tests/test_string.c
index 6eef4c2..e9e249f 100644
--- a/tests/test_string.c
+++ b/tests/test_string.c
@@ -6,10 +6,10 @@ void test_string(){
         printf("\e[96m-------------[test_string]-------------\n");
         char c[]="0123456789abcdef";
         string s=string_cpFromCharPtr(c);
-        printf("\e[92m\"%s\" -> string_cpFromCharPtr()\n",c);
+        printf("\e[92m\"%s\" \e[94m-> string_cpFromCharPtr()\n",c);
         if(s.length!=16) throw("string created with incorrect length");
         char* p=string_cpToCptr(s);
-        printf("\e[92mstring_cpToCptr() -> \"%s\"\n",p);
+        printf("\e[94mstring_cpToCptr() -> \e[92m\"%s\"\n",p);
         free(p);
         free(s.ptr);
     }));
diff --git a/tests/tests.h b/tests/tests.h
index 220ac56..edaa49f 100644
--- a/tests/tests.h
+++ b/tests/tests.h
@@ -8,4 +8,5 @@ void test_searchtree();
 void test_autoarr();
 void test_hashtable();
 void test_string();
-void test_dtsod();
\ No newline at end of file
+void test_dtsod();
+void test_safethrow();
\ No newline at end of file