diff --git a/include/cmd/args/arg_generic.hpp b/include/cmd/args/arg_generic.hpp
index fabfd09..2bbf324 100644
--- a/include/cmd/args/arg_generic.hpp
+++ b/include/cmd/args/arg_generic.hpp
@@ -1,10 +1,16 @@
 #pragma once
 
 #include <memory>
+#include <stdexcept>
+#include <string>
+#include <type_traits>
 
 #include "cmd/args/arg_base.hpp"
 #include "ast/ast_component.hpp"
 
+#include "lexer.hpp"
+#include "util/stringliteral.hpp"
+
 namespace fsh {
 
     template <typename T>
@@ -15,22 +21,33 @@ namespace fsh {
         Argument() {}
 
         virtual void svalue(const std::string& val, const Lexer::TokenType& type) override;
+
         virtual T&   gvalue() { return value; }
 
-      private:
+        bool gis_string_literal() { return is_string_literal; }
+
+      protected:
         bool is_string_literal; // Currently no getter
         T    value;
     };
 
     template <class T>
     void Argument<T>::svalue(const std::string& val, const Lexer::TokenType& type) {
-        if constexpr (std::is_same_v<T, std::string>) {
-            value = val;
-        } else {
+
+        is_string_literal = type == Lexer::TokenType::STRING_LITERAL;
+
+        if constexpr (std::is_same_v<T, StringLiteral>) {
+            if(type != Lexer::TokenType::STRING_LITERAL) {
+                throw std::invalid_argument("Incorrect type");
+            }
+        }
+
+        if constexpr (!std::is_same_v<T, std::string> && !std::is_base_of_v<std::string, T>) {
             std::stringstream ss_val(val);
             if (!(ss_val >> value)) { throw std::invalid_argument("Incorrect type"); }
+        } else {
+            value = val;
         }
-        is_string_literal = type == Lexer::TokenType::STRING_LITERAL;
     }
 
 }
\ No newline at end of file
diff --git a/include/cmd/args/arg_input.hpp b/include/cmd/args/arg_input.hpp
index 346b2cb..3aee7ff 100644
--- a/include/cmd/args/arg_input.hpp
+++ b/include/cmd/args/arg_input.hpp
@@ -4,19 +4,20 @@
 #include <sstream>
 
 #include "cmd/args/arg_base.hpp"
+#include "cmd/args/arg_generic.hpp"
 
 namespace fsh {
 
-    class ArgInput : public _Argument {
+    class ArgInput : public Argument<std::string> {
       public:
         static std::istream& get(std::shared_ptr<_Argument> a) {
-            return std::dynamic_pointer_cast<ArgInput>(a)->gvalue();
+            return std::dynamic_pointer_cast<ArgInput>(a)->gstream();
         }
 
         ArgInput() {}
 
         virtual void          svalue(const std::string& val, const Lexer::TokenType& type) override;
-        virtual std::istream& gvalue();
+        virtual std::istream& gstream();
 
       private:
         std::optional<std::stringstream> str;
diff --git a/include/cmd/args/arg_manager.hpp b/include/cmd/args/arg_manager.hpp
index 99d344f..a631f4f 100644
--- a/include/cmd/args/arg_manager.hpp
+++ b/include/cmd/args/arg_manager.hpp
@@ -30,11 +30,16 @@ namespace fsh {
             if (flags.find(id) != flags.end()) return Argument<T>::get(flags[id]);
             return std::make_optional<T>();
         }
+
         bool get(const std::string& id) { return flags.find(id) != flags.end(); }
 
         void push_arg(std::shared_ptr<_Argument> arg) { pos_argument.push_back(arg); }
         void push_flag(const std::string& id, std::shared_ptr<_Argument> arg = nullptr) { flags[id] = arg; }
 
+        unsigned int size() {
+            return pos_argument.size();
+        }
+
       private:
         PosArgs  pos_argument;
         FlagOpts flags;
diff --git a/include/cmd/cmd.hpp b/include/cmd/cmd.hpp
index 2af8a17..5c70eb7 100644
--- a/include/cmd/cmd.hpp
+++ b/include/cmd/cmd.hpp
@@ -8,6 +8,10 @@
 #include "cmd/cmd_misc.hpp"
 #include "cmd/cmd_time.hpp"
 #include "cmd/cmd_touch.hpp"
+#include "cmd/cmd_truncate.hpp"
+#include "cmd/cmd_tr.hpp"
+#include "cmd/cmd_prompt.hpp"
+#include "cmd/cmd_rm.hpp"
 #include "cmd/cmd_wc.hpp"
 
 namespace fsh {
@@ -21,7 +25,7 @@ namespace fsh {
         }
 
         Command& get(const std::string n) {
-            if (cmds.find(n) == cmds.end()) { throw std::runtime_error("Command not found"); }
+            if (cmds.find(n) == cmds.end()) { throw std::runtime_error("Command not found " + n); }
             return *(cmds[n]);
         }
 
@@ -30,13 +34,17 @@ namespace fsh {
       private:
         // Nove komande bi registrovali ovde:
         CommandRegistry() {
-            cmds["wc"]    = Command::register_cmd<CmdWc>();
-            cmds["date"]  = Command::register_cmd<CmdDate>();
-            cmds["time"]  = Command::register_cmd<CmdTime>();
-            cmds["echo"]  = Command::register_cmd<CmdEcho>();
-            cmds["exit"]  = Command::register_cmd<CmdExit>();
-            cmds["touch"] = Command::register_cmd<CmdTouch>();
-            cmds["debug"] = Command::register_cmd<CmdPrintTree>();
+            cmds["tr"]       = Command::register_cmd<CmdTr>();
+            cmds["rm"]       = Command::register_cmd<CmdRM>();
+            cmds["wc"]       = Command::register_cmd<CmdWc>();
+            cmds["date"]     = Command::register_cmd<CmdDate>();
+            cmds["time"]     = Command::register_cmd<CmdTime>();
+            cmds["echo"]     = Command::register_cmd<CmdEcho>();
+            cmds["exit"]     = Command::register_cmd<CmdExit>();
+            cmds["touch"]    = Command::register_cmd<CmdTouch>();
+            cmds["debug"]    = Command::register_cmd<CmdPrintTree>();
+            cmds["prompt"]   = Command::register_cmd<CmdPrompt>();
+            cmds["truncate"] = Command::register_cmd<CmdTruncate>();
         }
 
         std::unordered_map<std::string, std::unique_ptr<Command> > cmds;
diff --git a/include/cmd/cmd_base.hpp b/include/cmd/cmd_base.hpp
index aa7de5b..796ef10 100644
--- a/include/cmd/cmd_base.hpp
+++ b/include/cmd/cmd_base.hpp
@@ -12,12 +12,12 @@
 namespace fsh {
 
     class Command {
-
+      public:
         using FlagNode = std::optional<std::string>&;
         using ArgNodes = std::vector<std::shared_ptr<CommandArgumentNode> >;
 
-      public:
-        void execute(FlagNode flag, ArgNodes& vec, std::istream& in, std::ostream& out);
+        virtual void execute(FlagNode flag, ArgNodes& vec, std::istream& in, std::ostream& out, ArgFactory &arg_factory);
+        virtual void execute(FlagNode flag, ArgNodes& vec, std::istream& in, std::ostream& out);
 
         template <typename T>
         static std::unique_ptr<Command> register_cmd() {
diff --git a/include/cmd/cmd_echo.hpp b/include/cmd/cmd_echo.hpp
index 93e8742..88b77e2 100644
--- a/include/cmd/cmd_echo.hpp
+++ b/include/cmd/cmd_echo.hpp
@@ -15,7 +15,7 @@ namespace fsh {
         virtual void run(std::istream& in, std::ostream& out, ArgManager& args) override {
             std::string s;
             std::string o;
-            while (getline(in, s)) { o += s + "\n"; }
+            while (std::getline(in, s)) { o += s + "\n"; }
             out << o;
         }
     };
diff --git a/include/cmd/cmd_prompt.hpp b/include/cmd/cmd_prompt.hpp
new file mode 100644
index 0000000..70557df
--- /dev/null
+++ b/include/cmd/cmd_prompt.hpp
@@ -0,0 +1,26 @@
+#pragma once
+
+#include "cmd/cmd_base.hpp"
+#include "util/stringliteral.hpp"
+#include "fsh.hpp"
+#include <string>
+
+namespace fsh {
+
+    class CmdPrompt : public Command {
+
+      protected:
+        virtual void register_flags() override {
+            ArgFactory& factory = get_factory();
+            factory.add_rule<StringLiteral>(1);
+        }
+
+        virtual void run(std::istream& in, std::ostream& out, ArgManager& args) override {
+
+            std::string n_prompt = args.get<StringLiteral>(0).value();
+
+            fsh::instance().environment["PROMPT"] = n_prompt;
+        }
+    };
+
+}
\ No newline at end of file
diff --git a/include/cmd/cmd_rm.hpp b/include/cmd/cmd_rm.hpp
new file mode 100644
index 0000000..4b5c424
--- /dev/null
+++ b/include/cmd/cmd_rm.hpp
@@ -0,0 +1,26 @@
+#pragma once
+
+#include "cmd/cmd_base.hpp"
+#include <stdexcept>
+#include <string>
+
+namespace fsh {
+
+    class CmdRM : public Command {
+
+      protected:
+        virtual void register_flags() override {
+            ArgFactory& factory = get_factory();
+            factory.add_rule<std::string>(1);
+        }
+
+        virtual void run(std::istream& in, std::ostream& out, ArgManager& args) override {
+
+            if(std::remove(args.get<std::string>(0).value().c_str())) {
+                throw std::runtime_error("Could not delete file");
+            }
+
+        }
+    };
+
+}
\ No newline at end of file
diff --git a/include/cmd/cmd_tr.hpp b/include/cmd/cmd_tr.hpp
new file mode 100644
index 0000000..3da59ea
--- /dev/null
+++ b/include/cmd/cmd_tr.hpp
@@ -0,0 +1,74 @@
+#pragma once
+
+#include "cmd/args/arg.hpp"
+#include "cmd/args/arg_generic.hpp"
+#include "cmd/args/arg_input.hpp"
+#include "cmd/args/arg_manager.hpp"
+#include "cmd/cmd_base.hpp"
+#include "util/input.hpp"
+#include "util/stringliteral.hpp"
+#include <algorithm>
+#include <iostream>
+#include <memory>
+#include <stdexcept>
+#include <string>
+
+namespace fsh {
+
+    class CmdTr : public Command {
+      public:
+        virtual void execute(FlagNode flag, ArgNodes& vec, std::istream& in, std::ostream& out) override {
+            ArgFactory af;
+            switch (vec.size()) {
+                case 2: 
+                    af.add_rule<StringLiteral>(1);
+                case 1: 
+                    af.add_rule<StringLiteral>(1);
+                    break;
+                
+                default:
+                    af.add_input_rule();
+                    af.add_rule<StringLiteral>(1);
+                    af.add_rule<StringLiteral>(1);
+                    break;
+            }
+            Command::execute(flag, vec, in,out, af);
+        }
+
+      protected:
+
+        std::string replace_all(std::string str,const std::string &what,const std::string &with) {
+            if(what == "") throw std::runtime_error("\"\" cannot be used as what");
+
+            unsigned long long pos = str.find(what);
+
+            while(pos != std::string::npos) {
+                str.replace(pos,what.size(),with) ;
+                pos = str.find(what,pos+with.size());
+            }
+            return str;
+        }
+
+        virtual void run(std::istream& in, std::ostream& out, ArgManager& args) override {
+            std::string s;
+            std::string o;
+            std::string what = "";
+            std::string with = "";
+            while (std::getline(in, s)) { o += s + "\n"; }
+            
+            switch (args.size()) {
+                case 2:
+                    with = args.get<StringLiteral>(1).value();
+                case 1:
+                    what = args.get<StringLiteral>(0).value();
+                    break;
+                case 3:
+                    what = args.get<StringLiteral>(1).value();
+                    with = args.get<StringLiteral>(2).value();
+            }
+
+            out << replace_all(o,what,with);
+        }
+    };
+
+}
\ No newline at end of file
diff --git a/include/cmd/cmd_truncate.hpp b/include/cmd/cmd_truncate.hpp
new file mode 100644
index 0000000..39bc925
--- /dev/null
+++ b/include/cmd/cmd_truncate.hpp
@@ -0,0 +1,34 @@
+#pragma once
+
+#include "cmd/cmd_base.hpp"
+#include <fstream>
+#include <ios>
+#include <stdexcept>
+#include <string>
+
+namespace fsh {
+
+    class CmdTruncate : public Command {
+
+      protected:
+        virtual void register_flags() override {
+            ArgFactory& factory = get_factory();
+            factory.add_rule<std::string>(1);
+        }
+
+        virtual void run(std::istream& in, std::ostream& out, ArgManager& args) override {
+
+            std::string filename = args.get<std::string>(0).value();
+
+            if(!std::ifstream(filename, std::ios_base::in)) {
+                throw std::runtime_error("File does not exist");
+            }
+
+            if(!std::ofstream(filename, std::ios_base::out)) {
+                throw std::runtime_error("Failed to truncate");
+            }
+
+        }
+    };
+
+}
\ No newline at end of file
diff --git a/include/util/stringliteral.hpp b/include/util/stringliteral.hpp
new file mode 100644
index 0000000..31d48b3
--- /dev/null
+++ b/include/util/stringliteral.hpp
@@ -0,0 +1,13 @@
+#pragma once
+
+#include <string>
+
+namespace fsh {
+
+    class StringLiteral : public std::string {
+        public:
+            StringLiteral() : std::string() {}
+            StringLiteral(const std::string& str) : std::string(str) {}
+    };
+
+}
\ No newline at end of file