diff --git a/src/base/cptr.c b/src/base/cptr.c
index a4080fe..cba9814 100644
--- a/src/base/cptr.c
+++ b/src/base/cptr.c
@@ -46,4 +46,42 @@ bool cptr_endsWith(char* ptr, char* fragment){
     for(char cs=*ptr, cf=*fragment; cf; cs=*++ptr, cf=*++fragment)
         if(cs!=cf) return false;
     return true;
-}
\ No newline at end of file
+}
+
+void memcopy(void* from, void* to, uint32 size){
+    if(from==NULL || to==NULL)
+        throw(ERR_NULLPTR);
+    for(uint32 i=0; i<size; i++)
+        ((char*)to)[i]=*(char*)from+i;
+}
+
+char* __cptr_concat(uint16 n, ...){
+    char** strs=(char**)malloc(n*8);
+    uint32* lengths=malloc(n*4);
+    uint32 totalLength=0;
+
+    // reading args from va_list
+    va_list vl;
+    va_start(vl, n);
+    for(uint16 i=0; i<n; i++){
+        char* str=va_arg(vl,char*);
+        int16 length=cptr_length(str);
+        strs[i]=str;
+        lengths[i]=length;
+        totalLength+=length;
+    }
+    va_end(vl);
+
+    // allocating memory for output value
+    char* totality=malloc(totalLength+1);
+    const char* output=totality;
+    totality[totalLength]=0;
+    
+    // copying content of all strings to rezult
+    for(uint16 k=0; k<n; k++){
+        memcopy(strs[k], totality, lengths[k]);
+        totality+=lengths[k];
+    }
+    
+    return output;
+}
diff --git a/src/base/cptr.h b/src/base/cptr.h
index 6372931..bcf3252 100644
--- a/src/base/cptr.h
+++ b/src/base/cptr.h
@@ -22,6 +22,11 @@ bool cptr_startsWith(char* ptr, char* fragment);
 
 bool cptr_endsWith(char* ptr, char* fragment);
 
+void memcopy(void* from, void* to, uint32 size);
+
+char* __cptr_concat(uint16 n, ...);
+#define cptr_concat(STR...) __cptr_concat(count_args(STR), STR)
+
 #if __cplusplus
 }
 #endif
\ No newline at end of file
diff --git a/src/base/errors.h b/src/base/errors.h
index 324695e..7be9aa9 100644
--- a/src/base/errors.h
+++ b/src/base/errors.h
@@ -11,7 +11,7 @@ typedef enum ErrorId {
     SUCCESS, // not an error 
     ERR_MAXLENGTH, ERR_WRONGTYPE, ERR_WRONGINDEX, 
     ERR_NOTIMPLEMENTED, ERR_NULLPTR, ERR_ENDOFSTR, 
-    ERR_KEYNOTFOUND
+    ERR_KEYNOTFOUND, ERR_FORMAT
 } ErrorId;
 
 char* errname(ErrorId err);
diff --git a/src/base/kprint/kprint.c b/src/base/kprint/kprint.c
index 3ef337a..f099b69 100644
--- a/src/base/kprint/kprint.c
+++ b/src/base/kprint/kprint.c
@@ -19,8 +19,7 @@ Maybe __next_toString(kprint_format format, void* object){
         default: 
             safethrow("typeId is not set, can't autodetect type",;);
     }
-    try(ktDescriptor_get(format.typeId),mtd,;);
-    ktDescriptor typeDesc=*(ktDescriptor*)mtd.value.VoidPtr;
+    ktDescriptor typeDesc=ktDescriptor_get(format.typeId);
     if(!typeDesc.toString)
         safethrow("type descriptor doesnt have toString() func",;);
     try(typeDesc.toString(object, &format), mStr,;);
@@ -69,8 +68,7 @@ void kprint_setColor(kprint_format f){
 
 
 Maybe ksprint_ar(uint32 count, kprint_format format, ktId typeId, void* array){
-    try(ktDescriptor_get(format.typeId),mtd,;);
-    ktDescriptor typeDesc=*(ktDescriptor*)mtd.value.VoidPtr;
+    ktDescriptor typeDesc=ktDescriptor_get(format.typeId);
     if(!typeDesc.toString)
         safethrow("type descriptor doesnt have toString() func",;);
     StringBuilder* strb=StringBuilder_create();
diff --git a/src/base/kprint/kprint.h b/src/base/kprint/kprint.h
index 6236fec..5668638 100644
--- a/src/base/kprint/kprint.h
+++ b/src/base/kprint/kprint.h
@@ -8,67 +8,54 @@ extern "C" {
 #include "kprint_colors.h"
 #include "kprint_format.h"
 
-#define __count_args(\
-    a0, a1, a2, a3, a4, a5, a6, a7,\
-    a8, a9, a10,a11,a12,a13,a14,a15,\
-    a16,a17,a18,a19,a20,a21,a22,a23,\
-    a24,a25,a26,a27,a28,a29,a30,a31,\
-    a32) a32
-#define count_args(ARGS...) __count_args(\
-    ARGS,\
-    32,31,30,29,28,27,26,25,\
-    24,23,22,21,20,19,18,17,\
-    16,15,14,13,12,11,10,9,\
-    8, 7, 6, 5, 4, 3, 2, 1, 0)
-
 #define __kprint_argsToFormats8(\
-    a0, a1, a2, a3, a4, a5, a6, a7)\
-    (kprint_format[]{ a0,a2,a4,a6 })
+    a0, a1, a2, a3, a4, a5, a6, a7,...)\
+    ((int32[]){ a0,a2,a4,a6 })
 #define __kprint_argsToObjects8(\
-    a0, a1, a2, a3, a4, a5, a6, a7)\
-    (void*[]{ a1,a3,a5,a7 })
+    a0, a1, a2, a3, a4, a5, a6, a7,...)\
+    ((void*[]){ &a1,&a3,&a5,&a7 })
     
 #define __kprint_argsToFormats16(\
     a0, a1, a2, a3, a4, a5, a6, a7,\
-    a8, a9, a10,a11,a12,a13,a14,a15)\
-    (kprint_format[]{ a0,a2,a4,a6,a8,a10,a12,a14 })
+    a8, a9, a10,a11,a12,a13,a14,a15,...)\
+    ((int32[]){ a0,a2,a4,a6,a8,a10,a12,a14 })
 #define __kprint_argsToObjects16(\
     a0, a1, a2, a3, a4, a5, a6, a7,\
-    a8, a9, a10,a11,a12,a13,a14,a15)\
-    (void*[]{ a1,a3,a5,a7,a9,a11,a13,a15 })
-    
+    a8, a9, a10,a11,a12,a13,a14,a15,...)\
+    ((void*[]){ &a1,&a3,&a5,&a7,&a9,&a11,&a13,&a15 })
+
 #define __kprint_argsToFormats32(\
     a0, a1, a2, a3, a4, a5, a6, a7,\
     a8, a9, a10,a11,a12,a13,a14,a15,\
     a16,a17,a18,a19,a20,a21,a22,a23,\
-    a24,a25,a26,a27,a28,a29,a30,a31)\
-    (kprint_format[]{ a0,a2,a4,a6,a8,a10,a12,a14,a16,a18,a20,a22,a24,a26,a28,a30 }
+    a24,a25,a26,a27,a28,a29,a30,a31,...)\
+    ((int32[]){ a0,a2,a4,a6,a8,a10,a12,a14,a16,a18,a20,a22,a24,a26,a28,a30 })
 #define __kprint_argsToObjects32(\
     a0, a1, a2, a3, a4, a5, a6, a7,\
     a8, a9, a10,a11,a12,a13,a14,a15,\
     a16,a17,a18,a19,a20,a21,a22,a23,\
-    a24,a25,a26,a27,a28,a29,a30,a31)\
-    (void*[]{ a1,a3,a5,a7,a9,a11,a13,a15,a17,a19,a21,a23,a25,a27,a29,a31 })
+    a24,a25,a26,a27,a28,a29,a30,a31,...)\
+    ((void*[]){ &a1,&a3,&a5,&a7,&a9,&a11,&a13,&a15,&a17,&a19,&a21,&a23,&a25,&a27,&a29,&a31 })
 
 #define __32zeroes 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
 
-#define __kprint_argsToArrs(COUNT,ARGS...)(\
-    (COUNT<=8 __kprint_argsToFormats8(ARGS,__32zeroes) :\
-    COUNT<=16 __kprint_argsToFormats16(ARGS,__32zeroes) :\
-    __kprint_argsToFormats32(ARGS,__32zeroes)),\
-    (COUNT<=8 __kprint_argsToObjects8(ARGS,__32zeroes) :\
-    COUNT<=16 __kprint_argsToObjects16(ARGS) :\
-    __kprint_argsToObjects32(ARGS,__32zeroes))
+#define __kprint_argsToArrs(COUNT,ARGS...)\
+    (COUNT<=8 ? __kprint_argsToFormats8(ARGS) :\
+    COUNT<=16 ? __kprint_argsToFormats16(ARGS) :\
+    __kprint_argsToFormats32(ARGS)),\
+    (COUNT<=8 ? __kprint_argsToObjects8(ARGS) :\
+    COUNT<=16 ? __kprint_argsToObjects16(ARGS) :\
+    __kprint_argsToObjects32(ARGS))
 
 
-Maybe __ksprint(uint8 n, kprint_format* formats, void** objects);
-#define ksprint(ARGS...) __ksprint(count_args(ARGS), __kprint_argsToArrs(count_args(ARGS),ARGS))
+Maybe __ksprint(uint8 n, int32* formats, void** objects);
+#define ksprint(ARGS...) __ksprint(count_args(ARGS), __kprint_argsToArrs(count_args(ARGS),ARGS, __32zeroes))
 
-Maybe __kfprint(FILE* fd, uint8 n, kprint_format* formats, void** objects);
-#define kfprint(FD, ARGS...) __kfprint(FD, count_args(ARGS), __kprint_argsToArrs(count_args(ARGS),ARGS))
+Maybe __kfprint(FILE* fd, uint8 n, int32* formats, void** objects);
+#define kfprint(FD, ARGS...) __kfprint(FD, count_args(ARGS), __kprint_argsToArrs(count_args(ARGS),ARGS, __32zeroes))
 
-void __kprint(uint8 n, kprint_format* formats, void** objects);
-#define kprint(ARGS...) __kprint(count_args(ARGS), __kprint_argsToArrs(count_args(ARGS),ARGS))
+void __kprint(uint8 n, int32* formats, void** objects);
+#define kprint(ARGS...) __kprint(count_args(ARGS), __kprint_argsToArrs(count_args(ARGS),ARGS, __32zeroes))
 
 // can take (bgColor | fgColor) 
 void kprint_setColor(kprint_format f);
diff --git a/src/base/kprint/kprint_format.h b/src/base/kprint/kprint_format.h
index 1087c71..6bbce44 100644
--- a/src/base/kprint/kprint_format.h
+++ b/src/base/kprint/kprint_format.h
@@ -4,6 +4,7 @@
 extern "C" {
 #endif
 
+#include "../std.h"
 #include "../type_system/ktId.h"
 
 typedef enum kprint_dataFormat{
@@ -30,16 +31,18 @@ typedef enum kprint_dataFormat{
     kprint_fmtUppercase=0x10000000
 } kprint_dataFormat;
 
-
-typedef struct {
-    unsigned char fgColorChanged : 1;
-    unsigned char bgColorChanged : 1;
-    unsigned char withPrefix : 1;
-    unsigned char uppercase : 1;
-    unsigned char fgColor : 4;
-    unsigned char bgColor : 4;
-    unsigned char dataFmt : 4;
-    ktId typeId;
+typedef union {
+    int32 i32;
+    struct { 
+        unsigned char fgColorChanged : 1;
+        unsigned char bgColorChanged : 1;
+        unsigned char withPrefix : 1;
+        unsigned char uppercase : 1;
+        unsigned char fgColor : 4;
+        unsigned char bgColor : 4;
+        unsigned char dataFmt : 4;
+        ktId typeId;
+    };
 } kprint_format;
 
 #if __cplusplus
diff --git a/src/base/std.h b/src/base/std.h
index be41eec..061ed62 100644
--- a/src/base/std.h
+++ b/src/base/std.h
@@ -62,6 +62,20 @@ typedef double float64;
     #define sprintf_s(BUF, BUFSIZE, FORMAT, ...) sprintf(BUF, FORMAT, ## __VA_ARGS__)
 #endif
 
+
+#define __count_args(\
+    a0, a1, a2, a3, a4, a5, a6, a7,\
+    a8, a9, a10,a11,a12,a13,a14,a15,\
+    a16,a17,a18,a19,a20,a21,a22,a23,\
+    a24,a25,a26,a27,a28,a29,a30,a31,\
+    a32,...) a32
+#define count_args(ARGS...) __count_args(\
+    ARGS,\
+    32,31,30,29,28,27,26,25,\
+    24,23,22,21,20,19,18,17,\
+    16,15,14,13,12,11,10,9,\
+    8, 7, 6, 5, 4, 3, 2, 1, 0)
+
 #if __cplusplus
 }
 #endif
\ No newline at end of file
diff --git a/src/base/type_system/base_toString.c b/src/base/type_system/base_toString.c
new file mode 100644
index 0000000..7b47bb1
--- /dev/null
+++ b/src/base/type_system/base_toString.c
@@ -0,0 +1,156 @@
+#include "base_toString.h"
+#include "../cptr.h"
+#include "../kprint/kprint_format.h"
+
+char* toString_int(int64 n){
+    int64 d=n;
+    char str[32];
+    uint8 i=sizeof(str);
+    str[--i]=0;
+    while(d!=0){
+        str[--i]='0' + d%10;
+        d/=10;
+    }
+    if(n>>63)
+        str[--i]='-';
+    return cptr_copy((char*)str+i);
+}
+
+char* toString_uint(uint64 n, bool withPostfix, bool uppercase){
+    uint64 d=n;
+    char str[32];
+    uint8 i=sizeof(str);
+    str[--i]=0;
+    if(withPostfix)
+        str[--i]= uppercase ? 'U' : 'u';
+    while(d!=0){
+        str[--i]='0' + d%10;
+        d/=10;
+    }
+    return cptr_copy((char*)str+i);
+}
+
+char* toString_float(float64 n, bool withPostfix, bool uppercase){
+    int64 d=n;
+    float64 r=n-d;
+    char* strint=toString_int(d);
+    char strfract[32];
+    uint8 i=0;
+    strfract[i++]='.';
+    while(r!=0){
+        r*=10.0;
+        char fc=r;
+        strfract[i++]=fc;
+        r-=fc;
+    }
+    if(withPostfix)
+        strfract[i++]= uppercase ? 'F' : 'f';
+    strfract[i]=0;
+    char* str=cptr_concat(strint, strfract);
+    free(strint);
+    return str;
+}
+
+char* toString_bin(char* bytes, uint32 size, bool withPrefix){
+    char* str=malloc(size*8+1);
+    uint32 cn=0;
+    if(withPrefix){
+        str[cn++]='0';
+        str[cn++]='b';
+    }
+    for(uint32 bn=0; bn<size; bn++){
+        char byte=bytes[bn];
+        for(uint8 i=0; i<8; i++)
+            str[cn++]='0' + (byte & (char)128>>i);
+    }
+    str[cn]=0;
+    return str;
+}
+
+char _4bitsHex(uint8 u, bool uppercase){
+    switch(u){
+        case 0: case 1: case 2: case 3: case 4:
+        case 5: case 6: case 7: case 8: case 9:
+            return '0'+u;
+        case 0xA: case 0xB: case 0xC: 
+        case 0xD: case 0xE: case 0xF:
+            return (uppercase ? 'A'-10 : 'a'-10) + u;
+        default: return 219;
+    }
+}
+
+char* toString_hex(char* bytes, uint32 size, bool withPrefix, bool uppercase){
+    char* str=malloc(size*2);
+    uint32 cn=0;
+    if(withPrefix){
+        str[cn++]='0';
+        str[cn++]='x';
+    }
+    for(uint32 bn=0; bn<size; bn++){
+        char byte=bytes[bn];
+        str[cn++]=_4bitsHex(byte%16, uppercase);
+        str[cn++]=_4bitsHex(byte/16, uppercase);
+    }
+    str[cn]=0;
+    return str;
+}
+
+
+#define __toString_int_def(BITS) char* __toString_int##BITS(void* _n, int32 _f){\
+    kprint_format f=*(kprint_format*)&_f;\
+    switch(f.dataFmt | (uint32)0){\
+        case kprint_fmtInt:\
+            int##BITS n=*(int##BITS*)_n;\
+            return toString_int(n);\
+        case kprint_fmtBin:\
+            return toString_bin(_n, BITS/8, f.withPrefix);\
+        case kprint_fmtHex:\
+            return toString_hex(_n, BITS/8, f.withPrefix, f.uppercase);\
+        default:\
+            printf("\n%u\n", f.dataFmt);\
+            throw(ERR_FORMAT);\
+            return NULL;\
+    }\
+}
+__toString_int_def(8)
+__toString_int_def(16)
+__toString_int_def(32)
+__toString_int_def(64)
+
+#define __toString_uint_def(BITS) char* __toString_uint##BITS(void* _n, int32 _f){\
+    kprint_format f=*(kprint_format*)&_f;\
+    switch(f.dataFmt | (uint32)0){\
+        case kprint_fmtUInt:\
+            uint##BITS n=*(uint##BITS*)_n;\
+            return toString_uint(n, f.withPrefix, f.uppercase);\
+        case kprint_fmtBin:\
+            return toString_bin(_n, BITS/8, f.withPrefix);\
+        case kprint_fmtHex:\
+            return toString_hex(_n, BITS/8, f.withPrefix, f.uppercase);\
+        default:\
+            printf("\n%u\n", f.dataFmt);\
+            throw(ERR_FORMAT);\
+            return NULL;\
+    }\
+}
+__toString_uint_def(8)
+__toString_uint_def(16)
+__toString_uint_def(32)
+__toString_uint_def(64)
+
+#define __toString_float_def(BITS) char* __toString_float##BITS(void* _n, int32 _f){\
+    kprint_format f=*(kprint_format*)&_f;\
+    switch(f.dataFmt | (uint32)0){\
+        case kprint_fmtFloat:\
+            float##BITS n=*(float##BITS*)_n;\
+            return toString_float(n, f.withPrefix, f.uppercase);\
+        case kprint_fmtBin:\
+            return toString_bin(_n, BITS/8, f.withPrefix);\
+        case kprint_fmtHex:\
+            return toString_hex(_n, BITS/8, f.withPrefix, f.uppercase);\
+        default:\
+            printf("\n%u\n", f.dataFmt);\
+            throw(ERR_FORMAT);\
+            return NULL;\
+    }\
+}
diff --git a/src/base/type_system/base_toString.h b/src/base/type_system/base_toString.h
new file mode 100644
index 0000000..def1d4d
--- /dev/null
+++ b/src/base/type_system/base_toString.h
@@ -0,0 +1,32 @@
+#pragma once
+
+#if __cplusplus
+extern "C" {
+#endif
+
+#include "../errors.h"
+
+// functions for base types
+char* toString_int(int64 n);
+char* __toString_int8(void* n, int32 fmt);
+char* __toString_int16(void* n, int32 fmt);
+char* __toString_int32(void* n, int32 fmt);
+char* __toString_int64(void* n, int32 fmt);
+
+char* toString_uint(uint64 n, bool withPostfix, bool uppercase);
+char* __toString_uint8(void* n, int32 fmt);
+char* __toString_uint16(void* n, int32 fmt);
+char* __toString_uint32(void* n, int32 fmt);
+char* __toString_uint64(void* n, int32 fmt);
+
+char* toString_float(float64 n, bool withPostfix, bool uppercase); // very bad implimentation
+char* __toString_float32(void* n, int32 fmt);
+char* __toString_float64(void* n, int32 fmt);
+
+// universal functions
+char* toString_bin(char* bytes, uint32 size, bool withPrefix);
+char* toString_hex(char* bytes, uint32 size, bool withPrefix, bool uppercase);
+
+#if __cplusplus
+}
+#endif
\ No newline at end of file
diff --git a/src/base/type_system/init.c b/src/base/type_system/init.c
index 755756a..3e964dc 100644
--- a/src/base/type_system/init.c
+++ b/src/base/type_system/init.c
@@ -3,6 +3,7 @@
 #include "../../SearchTree/SearchTree.h"
 #include "../../Hashtable/Hashtable.h"
 #include "../../String/StringBuilder.h"
+#include "base_toString.h"
 
 void ktDescriptors_initKerepTypes(){
     // null
diff --git a/src/base/type_system/ktDescriptor.h b/src/base/type_system/ktDescriptor.h
index 907d002..9fb42d1 100644
--- a/src/base/type_system/ktDescriptor.h
+++ b/src/base/type_system/ktDescriptor.h
@@ -5,7 +5,6 @@ extern "C" {
 #endif
 
 #include "../std.h"
-#include "../errors.h"
 #include "ktId.h"
 
 typedef struct ktDescriptor{
@@ -13,8 +12,7 @@ typedef struct ktDescriptor{
     ktId id;
     uint16 size;
     void (*freeMembers)(void*); // NULL or function which frees all struct members
-    ///@return Maybe<char*>
-    Maybe (*toString)(void*, int32); // NULL or function which generates string representaion of object
+    char* (*toString)(void* obj, int32 fmt); // NULL or function which generates string representaion of object
 } ktDescriptor;
 
 #if __cplusplus
diff --git a/src/base/type_system/kt_functions.c b/src/base/type_system/kt_functions.c
index c183ff0..1f85eea 100644
--- a/src/base/type_system/kt_functions.c
+++ b/src/base/type_system/kt_functions.c
@@ -58,7 +58,7 @@ void ktDescriptors_endInit(){
     printf("\e[92minitialized %u type descriptors\n", ktId_last);
 }
 
-void __kt_register(char* name, int16 size, void (*freeMembers)(void*), Maybe (*toString)(void*, int32)){
+void __kt_register(char* name, int16 size, void (*freeMembers)(void*), char* (*toString)(void*, int32)){
     ktDescriptor typeDesc={
         .name=name,
         .size=size,
@@ -69,7 +69,10 @@ void __kt_register(char* name, int16 size, void (*freeMembers)(void*), Maybe (*t
     Autoarr_add(__ktDescriptors, typeDesc);
 }
 
-Maybe ktDescriptor_get(ktId id){
-    if(id>ktId_last) safethrow("invalid type id",;);
-    return SUCCESS(UniStack(ktId_ktDescriptorPtr, &typeDescriptors[id]));
+ktDescriptor ktDescriptor_get(ktId id){
+    if(id>ktId_last) {
+        printf("\n%u\n",id);
+        throw("invalid type id");
+    }
+    return typeDescriptors[id];
 }
diff --git a/src/base/type_system/kt_functions.h b/src/base/type_system/kt_functions.h
index b1e588f..cdf5359 100644
--- a/src/base/type_system/kt_functions.h
+++ b/src/base/type_system/kt_functions.h
@@ -10,7 +10,7 @@ extern "C" {
 
 
 extern ktId ktId_last;
-void __kt_register(char* name, int16 size, void (*freeMembers)(void*), Maybe (*toString)(void*, int32));
+void __kt_register(char* name, int16 size, void (*freeMembers)(void*), char* (*toString)(void*, int32));
 
 #define kt_register(TYPE, ID_VAR_NAME, FREE_MEMBERS_FUNC, TO_STRING_FUNC)\
     __kt_register(#ID_VAR_NAME, sizeof(TYPE), FREE_MEMBERS_FUNC, TO_STRING_FUNC);\
@@ -18,9 +18,9 @@ void __kt_register(char* name, int16 size, void (*freeMembers)(void*), Maybe (*t
 
 void ktDescriptors_beginInit();
 void ktDescriptors_endInit();
-/// @param id id of registered type 
-/// @return Maybe<ktDescriptor*>
-Maybe ktDescriptor_get(ktId id);
+
+/// @param id id of registered type
+ktDescriptor ktDescriptor_get(ktId id);
 
 
 ktId_declare(Null);
diff --git a/src/base/type_system/unitype.c b/src/base/type_system/unitype.c
index d4115cd..7bf9f1b 100644
--- a/src/base/type_system/unitype.c
+++ b/src/base/type_system/unitype.c
@@ -4,8 +4,7 @@ ktId_define(Unitype);
 ktId_define(UnitypePtr);
 
 void Unitype_free(Unitype u){
-    tryLast(ktDescriptor_get(u.typeId), mType);
-    ktDescriptor type=*(ktDescriptor*)mType.value.VoidPtr;
+    ktDescriptor type=ktDescriptor_get(u.typeId);
     if(type.freeMembers)
         type.freeMembers(u.VoidPtr);
     if(u.allocatedInHeap)
@@ -13,11 +12,23 @@ void Unitype_free(Unitype u){
 }
 void __UnitypePtr_free(void* u) { Unitype_free(*(Unitype*)u); }
 
+char* toString_Unitype(void* _u, int32 fmt){
+    Unitype* u=_u;
+    ktDescriptor type=ktDescriptor_get(u->typeId);
+    char* valuestr=type.toString(_u, fmt);
+    char* rezult=cptr_concat("{ type: ", type.name,
+        ", allocated on heap: ", (u->allocatedInHeap ? "true" : "false"),
+        ", value:", valuestr, " }");
+    free(valuestr);
+    return rezult;
+}
+
+
+
 #define BUFSIZE 64
 char* sprintuni(Unitype v){
     char* buf=malloc(BUFSIZE);
-    tryLast(ktDescriptor_get(v.typeId), mType);
-    ktDescriptor type=*(ktDescriptor*)mType.value.VoidPtr;
+    ktDescriptor type=ktDescriptor_get(v.typeId);
     if(v.typeId==ktId_Null)
         sprintf_s(buf, BUFSIZE, "{Null}");
     else if(v.typeId==ktId_Float64)