added help command

Author: Pankaja-Suganda

CMakeLists.txt

@@ -5,7 +5,7 @@ project(argparser)
 set(ARGPARSER_DIR "${CMAKE_CURRENT_SOURCE_DIR}/argparser")
 set(TEST_DIR      "${CMAKE_CURRENT_SOURCE_DIR}/test")
 
-set(TEST_ENABLE   ON)
+set(TEST_ENABLE   OFF)
 
 if(TEST_ENABLE)
     # Add test-related configurations or dependencies here

README.md

@@ -37,7 +37,10 @@ To use ArgParser in your C++ program, include the `argparser.h` header file and
 #include <argparser.h>
 
 int main(int argc, char* argv[]) {
-    ArgParser parser;
+    ArgParser parser(
+        "Argument Parser v1.1",                                      // Project name
+        "This project can be used to parse command line arguments"   // Description
+    );
 
     // Add arguments
     parser.addArgument("boolArg",   "-b", "--bool",   "Bool argument",   false);
@@ -60,6 +63,53 @@ int main(int argc, char* argv[]) {
 }
 ```
 
+## Help Command
+To display help information, use the following commands:
+
+```cmd
+./<exe-name>.exe -h 
+```
+or
+```cmd
+./<exe-name>.exe --help
+```
+
+Upon execution, it will output:
+```
+Argument Parser v1.1
+
+DESCRIPTION:
+        This project can be used to parse command line arguments
+USAGE:
+        -b, --bool      : This is a flag argument
+        -d, --double    : This is a double argument
+        -i, --int       : This is a int argument
+        -s, --string    : This is a string argument
+```
+Replace `<exe-name>` with the actual name of your executable. This section provides a quick guide on how users can access `help` information along with an example output showcasing the available command-line arguments.
+
+Otherthan that user can add own help command with built-in help command, then the user specified function will execute before `help` command.
+
+```cpp
+// Example user-specified callback
+void userSpecifiedCallback() {
+    printf("Executing user-specified callback before the built-in help command.");
+}
+
+int main(int argc, char* argv[]) {
+    ArgParser parser;
+
+    // Set user-specified callback for help
+    parser.setHelpCallback(userSpecifiedCallback);
+
+    // Parse command-line arguments
+    parser.parse(argc, argv);
+
+    // ... rest of the program
+    return 0;
+}
+```
+
 ## Examples
 
 Here are some examples demonstrating the usage of ArgParser:

argparser/include/argparser.h

@@ -12,7 +12,10 @@ using namespace std;
 
 class ArgParser {
 public:
+    using Callback = std::function<void()>;
+
     ArgParser();
+    ArgParser(const string& _name, const string& _description);
     ~ArgParser();
 
     template <typename T>
@@ -33,13 +36,19 @@ class ArgParser {
     }
 
     bool argExists(const string &name) const;
+    void setHelpCallback(const Callback& callback);
 
 private:
 
     bool precheck(const string& name, const string& shortcmd, const string& longcmd);
     void postcheck();
+    void help();
 
+    Callback help_callback;
     map<string, Argument*> args;
+
+    string name;
+    string description;
 };
 
 #endif // !_ARGPARSER_H_

argparser/include/argument.h

@@ -37,6 +37,7 @@ class Argument{
         string getName() const;
         string getShortCmd() const;
         string getLongCmd() const;
+        string getHelp() const;
         void setArgPosition(int position);
 
     private:

argparser/src/argdouble.cpp

@@ -17,7 +17,6 @@ ArgStatus DoubleArgument::loadValue(const string& arg, int pos){
 
         try{
             value = stod(arg);
-            printf("Float Value: %f\n", value);
             return PARSER_OK;
         } catch (const std::invalid_argument& e) {
             fprintf(stderr, "Error: %s is not a valid float.\n", arg.c_str());

argparser/src/argint.cpp

@@ -17,7 +17,6 @@ ArgStatus IntArgument::loadValue(const string& arg, int pos){
 
         try{
             value = stoi(arg);
-            printf("Int Value: %d\n", value);
             return PARSER_OK;
         } catch (const std::invalid_argument& e) {
             fprintf(stderr, "Error: %s is not a valid integer.\n", arg.c_str());

argparser/src/argparser.cpp

@@ -3,6 +3,7 @@
 #include <argint.h>
 #include <argdouble.h>
 #include <argstring.h>
+#include <string.h>
 // #define VALIDATE_STRING(x) \
 //     do { \
 //         if (x.empty()) { \
@@ -14,8 +15,20 @@
 #define VALIDATE_STRING(x)
 #define LONGCMD_STRING  "--"
 #define SHORTCMD_STRING '-'
+#define LONG_HELPCMD    "--help"
+#define SHORT_HELPCMD   "-h"
 
-ArgParser::ArgParser() {
+#define DEFAULT_PARSER_NAME        "Default Project Name"
+#define DEFAULT_PARSER_DESCRIPTION "Default Project Description"
+
+
+ArgParser::ArgParser()
+    : name(DEFAULT_PARSER_NAME), description(DEFAULT_PARSER_DESCRIPTION){
+
+}
+
+ArgParser::ArgParser(const string& _name, const string& _description)
+    : name(_name), description(_description){
 
 }
 
@@ -36,6 +49,10 @@ bool ArgParser::precheck(
         return false;
     }
 
+    if(longcmd == LONG_HELPCMD || shortcmd == SHORT_HELPCMD){
+        return false;
+    }
+
     for (const auto& argument : args) {
         if( argument.second->getName() == name || 
             argument.second->getLongCmd()  == longcmd || 
@@ -51,6 +68,30 @@ void ArgParser::postcheck(){
 
 }
 
+void ArgParser::help(){
+
+    if (help_callback) {
+        help_callback();
+    }
+
+    printf("%s\n\n", name.c_str());
+    printf("DESCRIPTION:\n\t%s\n", description.c_str());
+
+    printf("USAGE:\n");
+    for (const auto& argument : args) {
+        printf("\t%s, %s \t: %s\n", 
+            argument.second->getShortCmd().c_str(), 
+            argument.second->getLongCmd().c_str(),
+            argument.second->getHelp().c_str());
+    }
+
+    printf("\n");
+}
+
+void ArgParser::setHelpCallback(const Callback& callback){
+    help_callback = callback;
+}
+
 template <>
 ArgStatus ArgParser::addArgument<bool>(
     const string& name, 
@@ -164,6 +205,11 @@ ArgStatus ArgParser::parse(int argc, char* argv[]){
     Argument* temp = nullptr;
     ArgStatus ret = PARSER_ERROR;
 
+    if(strcmp(argv[1], LONG_HELPCMD) == PARSER_OK || strcmp(argv[1], SHORT_HELPCMD) == PARSER_OK){
+        help();
+        return PARSER_OK;
+    }
+
     for (int i = 0; i < argc; ++i) { 
         temp = find(argv[i]);
         if(temp != nullptr && !temp->status()) {

argparser/src/argstring.cpp

@@ -16,7 +16,6 @@ ArgStatus StringArgument::loadValue(const string& arg, int pos){
 
         if(!arg.empty()){
             value = arg;
-            printf("String Value: %s\n", value.c_str());
         }
         else{
             return PARSER_INVALID_ARGUMENT;

argparser/src/argument.cpp

@@ -40,6 +40,10 @@ string Argument::getLongCmd() const {
     return longcmd;
 }
 
+string Argument::getHelp() const {
+    return help;
+}
+
 void Argument::setArgPosition(int position){
     argpos = position;
 }

main.cpp

@@ -4,28 +4,40 @@ using namespace std;
 
 
 int main(int argc, char* argv[]){
-    ArgParser parser;
+    ArgParser parser(
+        "Argument Parser v1.1",                                      // Project name
+        "This project can be used to parse command line arguments"   // Description
+    );
 
-    parser.addArgument("debug",  "-d", "--debug",  "This is a flag argument",   false);
+    // char* sargv[] = { (char*)"program_name", 
+    //     (char*)"--int", (char*)"123",             // Int Argument
+    //     (char*)"--string", (char*)"Hello World",  // String Argument
+    //     (char*)"--bool",                          // Bool Argument
+    //     (char*)"--double", (char*)"65.343"};      // Double Argument
+    char* sargv[] = { (char*)"program_name",  (char*)"-h"};
+    int sargc = sizeof(sargv) / sizeof(sargv[0]);
+
+
+    parser.addArgument("bool",  "-b", "--bool",  "This is a flag argument",   false);
     parser.addArgument("int",    "-i", "--int",    "This is a int argument",    10);
     parser.addArgument("double", "-d", "--double", "This is a double argument", 0.0);
     parser.addArgument("string", "-s", "--string", "This is a string argument", "null");
     parser.parse(argc, argv);
-    parser.print();
+    //parser.print();
 
     auto intValue = parser.get<int>("int");
     auto doubleValue = parser.get<double>("double");
     auto stringValue = parser.get<string>("string");
 
-    printf("Int Value : %d\n", intValue);
-    printf("Double Value : %f\n", doubleValue);
-    printf("String Value : %s\n", stringValue.c_str());
 
-    if(parser.argExists("debug")){
-        printf("debug is there\n");
-    }
-    else{
-        printf("debug is not there\n");
-    }
+    // printf("Int Value : %d\n", intValue);
+    // printf("Double Value : %f\n", doubleValue);
+    // printf("String Value : %s\n", stringValue.c_str());
 
+    // if(parser.argExists("debug")){
+    //     printf("debug is there\n");
+    // }
+    // else{
+    //     printf("debug is not there\n");
+    // }
 }