diff --git a/include/parse.hpp b/include/parse.hpp
index 083e82a..6d02da6 100644
--- a/include/parse.hpp
+++ b/include/parse.hpp
@@ -26,6 +26,8 @@
 // bash specific
 #define ARRAY_ARG_END " \t\n;#()&|<>]"
 
+extern const std::vector<std::string> posix_cmdvar;
+extern const std::vector<std::string> bash_cmdvar;
 
 std::string import_file(std::string const& path);
 
diff --git a/include/processing.hpp b/include/processing.hpp
index 14e8904..083cde3 100644
--- a/include/processing.hpp
+++ b/include/processing.hpp
@@ -21,9 +21,6 @@ extern std::regex re_var_exclude;
 extern std::regex re_fct_exclude;
 extern const std::regex regex_null;
 
-// globals
-extern const std::vector<std::string> argvar_cmds;
-
 // Object maps (optimizations)
 extern countmap_t m_vars, m_vardefs, m_varcalls;
 extern countmap_t m_fcts, m_cmds;
@@ -46,6 +43,7 @@ void fctmap_get(_obj* in, std::regex const& exclude);
 void cmdmap_get(_obj* in, std::regex const& exclude);
 
 /** util functions **/
+std::string gen_json_struc(_obj* in);
 
 // gen regexes
 std::regex var_exclude_regex(std::string const& in, bool include_reserved);
diff --git a/include/struc.hpp b/include/struc.hpp
index c4dfc81..da1b95a 100644
--- a/include/struc.hpp
+++ b/include/struc.hpp
@@ -86,13 +86,13 @@ public:
     subarg_string, subarg_variable, subarg_subshell, subarg_arithmetic, subarg_manipulation, subarg_procsub,
     _variable,
     _redirect,
-    _arg, arg_procsub,
+    _arg,
     _arglist,
     _pipeline,
     _condlist,
     _list,
     arithmetic_operation, arithmetic_number, arithmetic_variable, arithmetic_parenthesis, arithmetic_subshell,
-    block_subshell, block_brace, block_main, block_cmd, block_function, block_case, block_if, block_for, block_while, block_until };
+    block_subshell, block_brace, block_main, block_cmd, block_function, block_case, block_if, block_for, block_while };
   _objtype type;
 
   virtual ~_obj() {;}
@@ -128,8 +128,10 @@ public:
 
   void insert(uint32_t i, subarg* val);
   void insert(uint32_t i, arg const& a);
+  void insert(uint32_t i, std::string const& in);
 
   inline void add(subarg* in) { sa.push_back(in); }
+  void add(std::string const& in);
   inline size_t size() { return sa.size(); }
 
   std::vector<subarg*> sa;
@@ -288,7 +290,7 @@ public:
 class cmd : public block
 {
 public:
-  cmd(arglist* in=nullptr) { type=_obj::block_cmd; args=in; }
+  cmd(arglist* in=nullptr) { type=_obj::block_cmd; args=in; is_cmdvar=false; }
   ~cmd() {
     if(args!=nullptr) delete args;
     for(auto it: var_assigns) {
@@ -309,6 +311,9 @@ public:
   // preceding var assigns
   std::vector<std::pair<variable*,arg*>> var_assigns;
 
+  // is a cmdvar type
+  bool is_cmdvar;
+
   // check if cmd is this (ex: unset)
   bool is(std::string const& in);
   // for var assigns in special cmds (export, unset, read, local)
diff --git a/include/util.hpp b/include/util.hpp
index 53f8d21..c183e40 100644
--- a/include/util.hpp
+++ b/include/util.hpp
@@ -128,6 +128,15 @@ void concat_sets(std::set<T>& a, std::set<T> const& b)
   }
 }
 
+template <class T>
+bool is_in_vector(T el, std::vector<T> vec)
+{
+  for(auto it: vec)
+    if(it == el)
+      return true;
+  return false;
+}
+
 std::set<std::string> prune_matching(std::set<std::string>& in, std::regex re);
 
 std::string delete_brackets(std::string const& in);
diff --git a/src/generate.cpp b/src/generate.cpp
index acf9e39..6ecb0d8 100644
--- a/src/generate.cpp
+++ b/src/generate.cpp
@@ -313,8 +313,29 @@ std::string cmd::generate(int ind)
 {
   std::string ret;
   // var assigns
+  if(is_cmdvar)
+  {
+    ret += args->generate(ind) + ' ';
+    for(auto it: var_assigns)
+    {
+      if(it.first != nullptr)
+        ret += it.first->generate(ind);
+      if(it.second != nullptr)
+        ret += it.second->generate(ind);
+      ret += ' ';
+    }
+    ret.pop_back();
+    return ret;
+  }
+
   for(auto it: var_assigns)
-    ret += it.first->generate(ind) + it.second->generate(ind) + ' ';
+  {
+    if(it.first != nullptr)
+      ret += it.first->generate(ind);
+    if(it.second != nullptr)
+      ret += it.second->generate(ind);
+    ret += ' ';
+  }
 
   if(args!=nullptr && args->size()>0)
   {
diff --git a/src/minimize.cpp b/src/minimize.cpp
index 4682a44..b15381d 100644
--- a/src/minimize.cpp
+++ b/src/minimize.cpp
@@ -62,22 +62,6 @@ bool r_replace_var(_obj* in, strmap_t* varmap)
       if(el!=varmap->end())
         t->varname = el->second;
     }; break;
-    case _obj::block_cmd: {
-      cmd* t = dynamic_cast<cmd*>(in);
-      for(auto it: t->subarg_vars())
-      {
-        string_subarg* tss = dynamic_cast<string_subarg*>(it);
-        auto el=varmap->find(get_varname(tss->val));
-        if(el!=varmap->end())
-        {
-          size_t tpos=tss->val.find('=');
-          if(tpos == std::string::npos)
-            tss->val = el->second;
-          else
-            tss->val = el->second + tss->val.substr(tpos);
-        }
-      }
-    }; break;
     default: break;
   }
   return true;
diff --git a/src/parse.cpp b/src/parse.cpp
index 675ebee..52aa04f 100644
--- a/src/parse.cpp
+++ b/src/parse.cpp
@@ -18,6 +18,9 @@ bool g_bash=false;
 #define PARSE_ERROR(str, i) ztd::format_error(str, "", in, i)
 
 // constants
+const std::vector<std::string> posix_cmdvar = { "export", "unset", "local", "read" };
+const std::vector<std::string> bash_cmdvar  = { "readonly", "declare", "typeset" };
+
 const std::vector<std::string> arithmetic_precedence_operators = { "!", "~", "+", "-" };
 const std::vector<std::string> arithmetic_operators = { "+", "-", "*", "/", "=", "==", "!=", "&", "|", "^", "<<", ">>", "&&", "||" };
 
@@ -339,7 +342,7 @@ std::pair<arg*, uint32_t> parse_arg(const char* in, uint32_t size, uint32_t star
             // add previous subarg
             std::string tmpstr=std::string(in+j, i-j);
             if(tmpstr!="")
-              ret->add(new string_subarg(tmpstr));
+              ret->add(tmpstr);
             // get arithmetic
             auto r=parse_arithmetic(in, size, i+3);
             arithmetic_subarg* tt = new arithmetic_subarg(r.first);
@@ -356,7 +359,7 @@ std::pair<arg*, uint32_t> parse_arg(const char* in, uint32_t size, uint32_t star
             // add previous subarg
             std::string tmpstr=std::string(in+j, i-j);
             if(tmpstr!="")
-              ret->add(new string_subarg(tmpstr));
+              ret->add(tmpstr);
             // get subshell
             auto r=parse_subshell(in, size, i+2);
             ret->add(new subshell_subarg(r.first, true));
@@ -367,7 +370,7 @@ std::pair<arg*, uint32_t> parse_arg(const char* in, uint32_t size, uint32_t star
             // add previous subarg
             std::string tmpstr=std::string(in+j, i-j);
             if(tmpstr!="")
-              ret->add(new string_subarg(tmpstr));
+              ret->add(tmpstr);
             // get manipulation
             auto r=parse_manipulation(in, size, i+2);
             r.first->quoted=true;
@@ -382,7 +385,7 @@ std::pair<arg*, uint32_t> parse_arg(const char* in, uint32_t size, uint32_t star
               // add previous subarg
               std::string tmpstr=std::string(in+j, i-j);
               if(tmpstr!="")
-                ret->add(new string_subarg(tmpstr));
+                ret->add(tmpstr);
               // add var
               ret->add(new variable_subarg(r.first, true));
               j = i = r.second;
@@ -413,7 +416,7 @@ std::pair<arg*, uint32_t> parse_arg(const char* in, uint32_t size, uint32_t star
         // add previous subarg
         std::string tmpstr=std::string(in+j, i-j);
         if(tmpstr!="")
-          ret->add(new string_subarg(tmpstr));
+          ret->add(tmpstr);
         // get arithmetic
         auto r=parse_arithmetic(in, size, i+3);
         ret->add(new arithmetic_subarg(r.first));
@@ -428,7 +431,7 @@ std::pair<arg*, uint32_t> parse_arg(const char* in, uint32_t size, uint32_t star
         // add previous subarg
         std::string tmpstr=std::string(in+j, i-j);
         if(tmpstr!="")
-          ret->add(new string_subarg(tmpstr));
+          ret->add(tmpstr);
         // get subshell
         auto r=parse_subshell(in, size, i+2);
         ret->add(new subshell_subarg(r.first, false));
@@ -439,7 +442,7 @@ std::pair<arg*, uint32_t> parse_arg(const char* in, uint32_t size, uint32_t star
         // add previous subarg
         std::string tmpstr=std::string(in+j, i-j);
         if(tmpstr!="")
-          ret->add(new string_subarg(tmpstr));
+          ret->add(tmpstr);
         // get manipulation
         auto r=parse_manipulation(in, size, i+2);
         ret->add(r.first);
@@ -453,7 +456,7 @@ std::pair<arg*, uint32_t> parse_arg(const char* in, uint32_t size, uint32_t star
           // add previous subarg
           std::string tmpstr=std::string(in+j, i-j);
           if(tmpstr!="")
-            ret->add(new string_subarg(tmpstr));
+            ret->add(tmpstr);
           // add var
           ret->add(new variable_subarg(r.first));
           j = i = r.second;
@@ -468,7 +471,7 @@ std::pair<arg*, uint32_t> parse_arg(const char* in, uint32_t size, uint32_t star
     // add string subarg
     std::string val=std::string(in+j, i-j);
     if(val != "")
-      ret->add(new string_subarg(val));
+      ret->add(val);
 
 #ifndef NO_PARSE_CATCH
   }
@@ -603,7 +606,7 @@ std::pair<redirect*, uint32_t> parse_redirect(const char* in, uint32_t size, uin
           std::string tmpparse=std::string(in+j, i-j);
           auto pval = parse_arg(tmpparse.c_str(), tmpparse.size(), 0, NULL);
           ret->target = pval.first;
-          ret->target->insert(0, new string_subarg(delimitor+"\n"));
+          ret->target->insert(0, delimitor+"\n");
         }
         else
         {
@@ -1099,6 +1102,93 @@ std::pair<function*, uint32_t> parse_function(const char* in, uint32_t size, uin
   return std::make_pair(ret, i);
 }
 
+// parse only var assigns
+uint32_t parse_cmd_varassigns(cmd* ret, const char* in, uint32_t size, uint32_t start, bool cmdassign=false, std::string const& cmd="")
+{
+  uint32_t i=start;
+  bool forbid_assign=false;
+  bool forbid_special=false;
+  if(cmdassign && (cmd == "read" || cmd == "unset") )
+    forbid_assign=true;
+  if(cmdassign && (forbid_special || cmd == "export") )
+    forbid_special=true;
+
+  while(i<size && !is_in(in[i], PIPELINE_END))
+  {
+    auto vp=parse_var(in, size, i, false, true);
+    if(vp.first != nullptr)
+      vp.first->definition=true;
+    if(vp.first != nullptr && vp.second<size && (in[vp.second] == '=' || word_eq("+=", in, size, vp.second) )) // is a var assign
+    {
+      if(forbid_assign)
+        throw PARSE_ERROR("Unallowed assign", i);
+      std::string strop = "=";
+      i=vp.second+1;
+      if( word_eq("+=", in, size, vp.second) ) // bash var+=
+      {
+        if(!g_bash)
+          throw PARSE_ERROR("bash specific: var+=", i);
+        if(forbid_special)
+          throw PARSE_ERROR("Unallowed special assign", i);
+        strop = "+=";
+        i++;
+      }
+      arg* ta;
+      if(in[i] == '(') // bash var=()
+      {
+        if(!g_bash)
+          throw PARSE_ERROR("bash specific: var=()", i);
+        if(forbid_special)
+          throw PARSE_ERROR("Unallowed special assign", i);
+        auto pp=parse_arg(in, size, i+1, ")");
+        ta=pp.first;
+        ta->insert(0,"(");
+        ta->add(")");
+        i=pp.second+1;
+      }
+      else if( is_in(in[i], ARG_END) ) // no value : give empty value
+      {
+        ta = new arg;
+      }
+      else
+      {
+        auto pp=parse_arg(in, size, i);
+        ta=pp.first;
+        i=pp.second;
+      }
+      ta->insert(0, strop);
+      ret->var_assigns.push_back(std::make_pair(vp.first, ta));
+      i=skip_chars(in, size, i, SPACES);
+    }
+    else
+    {
+      if(cmdassign)
+      {
+        if(vp.first != nullptr && is_in(in[vp.second], ARG_END) )
+        {
+          ret->var_assigns.push_back(std::make_pair(vp.first, nullptr));
+          i=vp.second;
+        }
+        else
+        {
+          delete vp.first;
+          auto pp=parse_arg(in, size, i);
+          ret->var_assigns.push_back(std::make_pair(nullptr, pp.first));
+          i=pp.second;
+        }
+        i=skip_chars(in, size, i, SPACES);
+      }
+      else
+      {
+        if(vp.first != nullptr)
+          delete vp.first;
+        break;
+      }
+    }
+  }
+  return i;
+}
+
 // must start at read char
 std::pair<cmd*, uint32_t> parse_cmd(const char* in, uint32_t size, uint32_t start)
 {
@@ -1110,42 +1200,22 @@ std::pair<cmd*, uint32_t> parse_cmd(const char* in, uint32_t size, uint32_t star
   {
 #endif
 ;
-    while(true) // parse var assigns
+    i=parse_cmd_varassigns(ret, in, size, i);
+
+    auto wp=get_word(in, size, i, ARG_END);
+    if(is_in_vector(wp.first, posix_cmdvar) || is_in_vector(wp.first, bash_cmdvar))
     {
-      auto vp=parse_var(in, size, i, false, true);
-      if(vp.first != nullptr && vp.second<size && in[vp.second] == '=') // is a var assign
-      {
-        vp.first->definition=true;
-        i=vp.second+1;
-        arg* ta;
-        if(g_bash && in[i] == '(')
-        {
-          auto pp=parse_arg(in, size, i+1, ")");
-          ta=pp.first;
-          ta->insert(0, new string_subarg("=(") );
-          ta->add(new string_subarg(")") );
-          i=pp.second+1;
-        }
-        else if( is_in(in[i], ARG_END) ) // no value : give empty value
-        {
-          ta = new arg("=");
-        }
-        else
-        {
-          auto pp=parse_arg(in, size, i);
-          ta=pp.first;
-          ta->insert(0, new string_subarg("="));
-          i=pp.second;
-        }
-        ret->var_assigns.push_back(std::make_pair(vp.first, ta));
-        i=skip_chars(in, size, i, " \t");
-      }
-      else
-      {
-        if(vp.first != nullptr)
-          delete vp.first;
-        break;
-      }
+      if(!g_bash && is_in_vector(wp.first, bash_cmdvar))
+        throw PARSE_ERROR("bash specific: "+wp.first, i);
+      if(ret->var_assigns.size()>0)
+        throw PARSE_ERROR("Unallowed preceding variables on "+wp.first, start);
+
+      ret->args = new arglist;
+      ret->args->add(new arg(wp.first));
+      ret->is_cmdvar=true;
+      i=skip_chars(in, size, wp.second, SPACES);
+
+      i=parse_cmd_varassigns(ret, in, size, i, true, wp.first);
     }
 
     if(!is_in(in[i], SPECIAL_TOKENS))
diff --git a/src/processing.cpp b/src/processing.cpp
index c9ebff4..3d8d920 100644
--- a/src/processing.cpp
+++ b/src/processing.cpp
@@ -13,10 +13,6 @@ std::regex re_fct_exclude;
 
 const std::regex regex_null;
 
-// globals
-
-const std::vector<std::string> argvar_cmds = { "export", "unset", "local", "read", "readonly", "declare" };
-
 // Object maps
 
 countmap_t m_vars, m_vardefs, m_varcalls;
@@ -158,15 +154,12 @@ std::string get_varname(arg* in)
 
 bool cmd_is_argvar(std::string const& in)
 {
-  for(auto it: argvar_cmds)
-    if(in == it)
-      return true;
-  return false;
+  return is_in_vector(in, posix_cmdvar) || is_in_vector(in, bash_cmdvar);
 }
 
 bool cmd::is_argvar()
 {
-  return cmd_is_argvar(this->firstarg_string());
+  return is_cmdvar;
 }
 
 bool cmd::is(std::string const& in)
@@ -248,8 +241,11 @@ void add_unset_variables(shmain* sh, std::regex const& exclude)
   {
     cmd* unset_cmd = new cmd;
     unset_cmd->add(new arg("unset"));
+    unset_cmd->is_cmdvar=true;
     for(auto it: m_vars)
-      unset_cmd->add(new arg(it.first));
+    {
+      unset_cmd->var_assigns.push_back(std::make_pair(new variable(it.first), nullptr));
+    }
     condlist* cl = new condlist(unset_cmd);
     sh->lst->cls.insert(sh->lst->cls.begin(), cl);
   }
@@ -276,18 +272,6 @@ bool r_get_var(_obj* in, countmap_t* defmap, countmap_t* callmap)
           (*callmap)[t->varname]++;
       }
     }; break;
-    case _obj::block_cmd: {
-      cmd* t = dynamic_cast<cmd*>(in);
-      if(t->is_argvar())
-      {
-        for(uint32_t i=1; i<t->args->size(); i++)
-        {
-          std::string varname=get_varname(t->args->args[i]);
-          if( varname != "" && !defmap->insert( std::make_pair(varname, 1) ).second )
-            (*defmap)[varname]++;
-        }
-      }
-    }; break;
     default: break;
   }
   return true;
@@ -301,9 +285,10 @@ bool r_get_unsets(_obj* in, set_t* unsets)
       cmd* t = dynamic_cast<cmd*>(in);
       if(t->is("unset"))
       {
-        for(uint32_t i=1; i<t->args->size(); i++)
+        for(auto it: t->var_assigns)
         {
-          unsets->insert(t->args->args[i]->string());
+          if(it.first != nullptr)
+            unsets->insert(it.first->varname);
         }
       }
     }; break;
@@ -379,37 +364,25 @@ bool r_delete_var(_obj* in, set_t* vars)
       {
         block* tb = t->cls[i]->first_block();
         bool to_delete=false;
+        bool has_deleted=false;
         if(tb != nullptr && tb->type == _obj::block_cmd)
         {
           cmd* c = dynamic_cast<cmd*>(tb);
 
           for(uint32_t j=0; j<c->var_assigns.size(); j++)
           {
-            if( vars->find(c->var_assigns[j].first->varname) != vars->end() )
+            if( c->var_assigns[j].first == nullptr || vars->find(c->var_assigns[j].first->varname) != vars->end() )
             {
-              delete c->var_assigns[j].first;
-              delete c->var_assigns[j].second;
+              if(c->var_assigns[j].first != nullptr)
+                delete c->var_assigns[j].first;
+              if(c->var_assigns[j].second != nullptr)
+                delete c->var_assigns[j].second;
               c->var_assigns.erase(c->var_assigns.begin()+j);
+              has_deleted=true;
               j--;
             }
           }
-
-          if(c->is_argvar())
-          {
-            for(uint32_t j=1; j<c->args->size(); j++)
-            {
-              std::string varname=get_varname(c->args->args[j]);
-              if( varname != "" && vars->find( varname ) != vars->end() )
-              {
-                delete c->args->args[j];
-                c->args->args.erase(c->args->args.begin()+j);
-                j--;
-              }
-            }
-            if(c->args->size()<=1)
-              to_delete=true;
-          }
-          if(c->var_assigns.size()<=0 && c->arglist_size()<=0)
+          if(has_deleted && c->var_assigns.size()<=0 && (c->arglist_size()<=0 || c->is_cmdvar) )
             to_delete=true;
 
         }
@@ -425,3 +398,374 @@ bool r_delete_var(_obj* in, set_t* vars)
   }
   return true;
 }
+
+std::string quote_string(std::string const& in)
+{
+  return '"' + stringReplace(in, "\"", "\\\"") + '"';
+}
+
+std::string gen_json(std::vector<std::pair<std::string,std::string>> const& vec)
+{
+  std::string ret;
+  for(auto it: vec)
+  {
+    ret += it.first + ":" + it.second + ',';
+  }
+  if(ret != "")
+    ret.pop_back();
+  return "{" + ret + "}";
+}
+
+std::string gen_json(std::vector<std::string> const& vec)
+{
+  std::string ret;
+  for(auto it: vec)
+  {
+    ret += it + ',';
+  }
+  if(ret != "")
+    ret.pop_back();
+  return "[" + ret + "]";
+}
+
+std::string boolstring(bool in)
+{
+  if(in)
+    return "true";
+  else
+    return "false";
+}
+
+std::string gen_json_struc(_obj* o)
+{
+  if(o==nullptr)
+    return "{}";
+  std::vector<std::pair<std::string,std::string>> vec;
+  switch(o->type)
+  {
+    case _obj::_variable :
+    {
+      variable* t = dynamic_cast<variable*>(o);
+      vec.push_back(std::make_pair(quote_string("type"), quote_string("variable") ) );
+      vec.push_back(std::make_pair(quote_string("varname"), quote_string(t->varname)));
+      vec.push_back(std::make_pair(quote_string("definition"), boolstring(t->definition)));
+      vec.push_back(std::make_pair(quote_string("index"), gen_json_struc(t->index)));
+      break;
+    }
+    case _obj::_redirect :
+    {
+      redirect* t = dynamic_cast<redirect*>(o);
+      vec.push_back(std::make_pair(quote_string("type"), quote_string("redirect") ) );
+      vec.push_back(std::make_pair(quote_string("op"), quote_string(t->op)));
+      vec.push_back(std::make_pair(quote_string("target"), gen_json_struc(t->target)));
+      break;
+    }
+    case _obj::_arg :
+    {
+      arg* t = dynamic_cast<arg*>(o);
+      vec.push_back(std::make_pair(quote_string("type"), quote_string("arg") ) );
+      std::vector<std::string> tvec;
+      for(auto it: t->sa)
+        tvec.push_back(gen_json_struc(it));
+      vec.push_back(std::make_pair(quote_string("sa"), gen_json(tvec)));
+      break;
+    }
+    case _obj::_arglist :
+    {
+      arglist* t = dynamic_cast<arglist*>(o);
+      vec.push_back(std::make_pair(quote_string("type"), quote_string("arglist") ) );
+      std::vector<std::string> tvec;
+      for(auto it: t->args)
+        tvec.push_back(gen_json_struc(it));
+      vec.push_back(std::make_pair(quote_string("args"), gen_json(tvec)));
+      break;
+    }
+    case _obj::_pipeline :
+    {
+      pipeline* t = dynamic_cast<pipeline*>(o);
+      vec.push_back(std::make_pair(quote_string("type"), quote_string("pipeline") ) );
+      vec.push_back(std::make_pair(quote_string("negated"), boolstring(t->negated) ) );
+      std::vector<std::string> tvec;
+      for(auto it: t->cmds)
+        tvec.push_back(gen_json_struc(it));
+      vec.push_back(std::make_pair(quote_string("cmds"), gen_json(tvec)));
+      break;
+    }
+    case _obj::_condlist :
+    {
+      condlist* t = dynamic_cast<condlist*>(o);
+      vec.push_back(std::make_pair(quote_string("type"), quote_string("condlist") ) );
+      vec.push_back(std::make_pair(quote_string("parallel"), boolstring(t->parallel) ) );
+      std::vector<std::string> tvec;
+      for(auto it: t->pls)
+        tvec.push_back(gen_json_struc(it));
+      vec.push_back(std::make_pair(quote_string("pls"), gen_json(tvec)));
+
+      std::vector<std::string> ttvec;
+      for(auto it: t->or_ops)
+      {
+        ttvec.push_back(boolstring(it));
+      }
+      vec.push_back(std::make_pair(quote_string("or_ops"), gen_json(ttvec)));
+      break;
+    }
+    case _obj::_list :
+    {
+      list* t = dynamic_cast<list*>(o);
+      vec.push_back(std::make_pair(quote_string("type"), quote_string("list") ) );
+      std::vector<std::string> tvec;
+      for(auto it: t->cls)
+        tvec.push_back(gen_json_struc(it));
+      vec.push_back(std::make_pair(quote_string("cls"), gen_json(tvec)));
+      break;
+    }
+    case _obj::block_subshell :
+    {
+      subshell* t = dynamic_cast<subshell*>(o);
+      vec.push_back(std::make_pair(quote_string("type"), quote_string("subshell") ) );
+
+      vec.push_back(std::make_pair(quote_string("lst"), gen_json_struc(t->lst)));
+
+      std::vector<std::string> tvec;
+      for(auto it: t->redirs)
+        tvec.push_back(gen_json_struc(it));
+      vec.push_back(std::make_pair(quote_string("redirs"), gen_json(tvec)));
+
+      break;
+    }
+    case _obj::block_brace :
+    {
+      brace* t = dynamic_cast<brace*>(o);
+      vec.push_back(std::make_pair(quote_string("type"), quote_string("brace") ) );
+
+      vec.push_back(std::make_pair(quote_string("lst"), gen_json_struc(t->lst)));
+
+      std::vector<std::string> tvec;
+      for(auto it: t->redirs)
+        tvec.push_back(gen_json_struc(it));
+      vec.push_back(std::make_pair(quote_string("redirs"), gen_json(tvec)));
+
+      break;
+    }
+    case _obj::block_main :
+    {
+      shmain* t = dynamic_cast<shmain*>(o);
+      vec.push_back(std::make_pair(quote_string("type"), quote_string("main") ) );
+      vec.push_back(std::make_pair(quote_string("shebang"), quote_string(t->shebang) ) );
+
+      vec.push_back(std::make_pair(quote_string("lst"), gen_json_struc(t->lst)));
+
+      std::vector<std::string> tvec;
+      for(auto it: t->redirs)
+        tvec.push_back(gen_json_struc(it));
+      vec.push_back(std::make_pair(quote_string("redirs"), gen_json(tvec)));
+
+      break;
+    }
+    case _obj::block_function :
+    {
+      function* t = dynamic_cast<function*>(o);
+      vec.push_back(std::make_pair(quote_string("type"), quote_string("function") ) );
+      vec.push_back(std::make_pair(quote_string("name"), quote_string(t->name) ) );
+
+      vec.push_back(std::make_pair(quote_string("lst"), gen_json_struc(t->lst)));
+
+      std::vector<std::string> tvec;
+      for(auto it: t->redirs)
+        tvec.push_back(gen_json_struc(it));
+      vec.push_back(std::make_pair(quote_string("redirs"), gen_json(tvec)));
+
+      break;
+    }
+    case _obj::block_cmd :
+    {
+      cmd* t = dynamic_cast<cmd*>(o);
+      vec.push_back(std::make_pair(quote_string("type"), quote_string("cmd") ) );
+
+      vec.push_back(std::make_pair(quote_string("args"), gen_json_struc(t->args)));
+      vec.push_back(std::make_pair(quote_string("is_cmdvar"), boolstring(t->is_cmdvar)));
+
+      std::vector<std::string> aa;
+      for(auto it: t->var_assigns)
+      {
+        std::vector<std::pair<std::string,std::string>> ttvec;
+        ttvec.push_back( std::make_pair(quote_string("var"), gen_json_struc(it.first)) );
+        ttvec.push_back( std::make_pair(quote_string("value"), gen_json_struc(it.second)) );
+        aa.push_back(gen_json(ttvec));
+      }
+      vec.push_back(std::make_pair( quote_string("var_assigns"), gen_json(aa)));
+
+      std::vector<std::string> tvec;
+      for(auto it: t->redirs)
+        tvec.push_back(gen_json_struc(it));
+      vec.push_back(std::make_pair(quote_string("redirs"), gen_json(tvec)));
+
+      break;
+    }
+    case _obj::block_case :
+    {
+      case_block* t = dynamic_cast<case_block*>(o);
+      vec.push_back(std::make_pair(quote_string("type"), quote_string("case") ) );
+
+      vec.push_back(std::make_pair(quote_string("carg"), gen_json_struc(t->carg)));
+
+      // [ {matchers:[], exec:{}} ]
+      // cases
+      std::vector<std::string> tt;
+      for(auto sc: t->cases)
+      {
+        std::vector<std::pair<std::string,std::string>> onecase;
+        std::vector<std::string> matchers;
+        for(auto it: sc.first)
+          matchers.push_back(gen_json_struc(it));
+        onecase.push_back( std::make_pair(quote_string("matcher"), gen_json(matchers)) );
+        onecase.push_back( std::make_pair(quote_string("execution"), gen_json_struc(sc.second)) );
+        tt.push_back(gen_json(onecase));
+      }
+      vec.push_back( std::make_pair(quote_string("cases"),gen_json(tt)) );
+
+      std::vector<std::string> tvec;
+      for(auto it: t->redirs)
+        tvec.push_back(gen_json_struc(it));
+      vec.push_back(std::make_pair(quote_string("redirs"), gen_json(tvec)));
+
+      break;
+    }
+    case _obj::block_if :
+    {
+      if_block* t = dynamic_cast<if_block*>(o);
+      vec.push_back(std::make_pair(quote_string("type"), quote_string("if") ) );
+
+      std::vector<std::string> condblocks;
+      // ifs
+      for(auto sc: t->blocks)
+      {
+        std::vector<std::pair<std::string, std::string> > one_cond;
+        one_cond.push_back(std::make_pair(quote_string("condition"), gen_json_struc(sc.first) ) );
+        one_cond.push_back(std::make_pair(quote_string("execution"), gen_json_struc(sc.second) ) );
+        condblocks.push_back(gen_json(one_cond));
+      }
+      vec.push_back( std::make_pair(quote_string("blocks"), gen_json(condblocks)) );
+      // else
+      vec.push_back(std::make_pair(quote_string("else_lst"), gen_json_struc(t->else_lst)));
+
+      std::vector<std::string> tvec;
+      for(auto it: t->redirs)
+        tvec.push_back(gen_json_struc(it));
+      vec.push_back(std::make_pair(quote_string("redirs"), gen_json(tvec)));
+
+      break;
+    }
+    case _obj::block_for :
+    {
+      for_block* t = dynamic_cast<for_block*>(o);
+      vec.push_back(std::make_pair(quote_string("type"), quote_string("for") ) );
+      vec.push_back(std::make_pair(quote_string("var"), gen_json_struc(t->var)));
+      vec.push_back(std::make_pair(quote_string("iter"), gen_json_struc(t->iter)));
+      vec.push_back(std::make_pair(quote_string("ops"), gen_json_struc(t->ops)));
+
+      std::vector<std::string> tvec;
+      for(auto it: t->redirs)
+        tvec.push_back(gen_json_struc(it));
+      vec.push_back(std::make_pair(quote_string("redirs"), gen_json(tvec)));
+
+      break;
+    }
+    case _obj::block_while :
+    {
+      while_block* t = dynamic_cast<while_block*>(o);
+      vec.push_back(std::make_pair(quote_string("type"), quote_string("while") ) );
+      vec.push_back(std::make_pair(quote_string("cond"), gen_json_struc(t->cond) ) );
+      vec.push_back(std::make_pair(quote_string("ops"), gen_json_struc(t->ops) ) );
+
+      std::vector<std::string> tvec;
+      for(auto it: t->redirs)
+        tvec.push_back(gen_json_struc(it));
+      vec.push_back(std::make_pair(quote_string("redirs"), gen_json(tvec)));
+
+      break;
+    }
+    case _obj::subarg_variable :
+    {
+      variable_subarg* t = dynamic_cast<variable_subarg*>(o);
+      vec.push_back(std::make_pair(quote_string("type"), quote_string("subarg_variable") ) );
+      vec.push_back(std::make_pair(quote_string("var"), gen_json_struc(t->var) ) );
+      break;
+    }
+    case _obj::subarg_subshell :
+    {
+      subshell_subarg* t = dynamic_cast<subshell_subarg*>(o);
+      vec.push_back(std::make_pair(quote_string("type"), quote_string("subarg_subshell") ) );
+      vec.push_back(std::make_pair(quote_string("sbsh"), gen_json_struc(t->sbsh) ) );
+      break;
+    }
+    case _obj::subarg_manipulation :
+    {
+      manipulation_subarg* t = dynamic_cast<manipulation_subarg*>(o);
+      vec.push_back(std::make_pair(quote_string("type"), quote_string("subarg_manipulation") ) );
+      vec.push_back(std::make_pair(quote_string("size"), boolstring(t->size) ) );
+      vec.push_back(std::make_pair(quote_string("var"), gen_json_struc(t->var) ) );
+      vec.push_back(std::make_pair(quote_string("manip"), gen_json_struc(t->manip) ) );
+      break;
+    }
+    case _obj::subarg_procsub :
+    {
+      procsub_subarg* t = dynamic_cast<procsub_subarg*>(o);
+      vec.push_back(std::make_pair(quote_string("type"), quote_string("subarg_procsub") ) );
+      vec.push_back(std::make_pair(quote_string("is_output"), boolstring(t->is_output) ) );
+      vec.push_back(std::make_pair(quote_string("sbsh"), gen_json_struc(t->sbsh) ) );
+      break;
+    }
+    case _obj::subarg_arithmetic :
+    {
+      arithmetic_subarg* t = dynamic_cast<arithmetic_subarg*>(o);
+      vec.push_back(std::make_pair(quote_string("type"), quote_string("subarg_arithmetic") ) );
+      vec.push_back(std::make_pair(quote_string("arith"), gen_json_struc(t->arith) ) );
+      break;
+    }
+    case _obj::subarg_string :
+    {
+      string_subarg* t = dynamic_cast<string_subarg*>(o);
+      vec.push_back(std::make_pair(quote_string("type"), quote_string("subarg_string") ) );
+      vec.push_back(std::make_pair(quote_string("val"), quote_string(t->val) ) );
+      break;
+    }
+    case _obj::arithmetic_variable :
+    {
+      variable_arithmetic* t = dynamic_cast<variable_arithmetic*>(o);
+      vec.push_back(std::make_pair(quote_string("type"), quote_string("arithmetic_variable") ) );
+      vec.push_back(std::make_pair(quote_string("var"), gen_json_struc(t->var) ) );
+      break;
+    }
+    case _obj::arithmetic_subshell :
+    {
+      subshell_arithmetic* t = dynamic_cast<subshell_arithmetic*>(o);
+      vec.push_back(std::make_pair(quote_string("type"), quote_string("arithmetic_subshell") ) );
+      vec.push_back(std::make_pair(quote_string("sbsh"), gen_json_struc(t->sbsh) ) );
+      break;
+    }
+    case _obj::arithmetic_operation :
+    {
+      operation_arithmetic* t = dynamic_cast<operation_arithmetic*>(o);
+      vec.push_back(std::make_pair(quote_string("type"), quote_string("arithmetic_operation") ) );
+      vec.push_back(std::make_pair(quote_string("val1"), gen_json_struc(t->val1) ) );
+      vec.push_back(std::make_pair(quote_string("val2"), gen_json_struc(t->val2) ) );
+      break;
+    }
+    case _obj::arithmetic_parenthesis :
+    {
+      parenthesis_arithmetic* t = dynamic_cast<parenthesis_arithmetic*>(o);
+      vec.push_back(std::make_pair(quote_string("type"), quote_string("arithmetic_parenthesis") ) );
+      vec.push_back(std::make_pair(quote_string("val"), gen_json_struc(t->val) ) );
+      break;
+    }
+    case _obj::arithmetic_number :
+    {
+      number_arithmetic* t = dynamic_cast<number_arithmetic*>(o);
+      vec.push_back(std::make_pair(quote_string("type"), quote_string("arithmetic_number") ) );
+      vec.push_back(std::make_pair(quote_string("val"), quote_string(t->val) ) );
+      break;
+    }
+  }
+  return gen_json(vec);
+}
diff --git a/src/resolve.cpp b/src/resolve.cpp
index 760ba8e..13dc5be 100644
--- a/src/resolve.cpp
+++ b/src/resolve.cpp
@@ -226,6 +226,10 @@ std::pair< std::vector<condlist*> , bool > resolve_condlist(condlist* in, shmain
 std::pair< std::vector<arg*> , bool > resolve_arg(arg* in, shmain* parent, bool forcequote=false)
 {
   std::vector<arg*> ret;
+  if(in == nullptr)
+  {
+    return std::make_pair(ret, false);
+  }
   arg* ta=nullptr;
   bool has_resolved=false;
   uint32_t j=0;
diff --git a/src/struc_helper.cpp b/src/struc_helper.cpp
index 83a0025..676084f 100644
--- a/src/struc_helper.cpp
+++ b/src/struc_helper.cpp
@@ -215,6 +215,15 @@ void condlist::prune_first_cmd()
 
 // add/extend
 
+void arg::insert(uint32_t i, std::string const& in)
+{
+  this->insert(i, new string_subarg(in));
+}
+void arg::add(std::string const& in)
+{
+  this->add(new string_subarg(in));
+}
+
 void arg::insert(uint32_t i, subarg* val)
 {
   sa.insert(sa.begin()+i, val);