Thread: Calling functions via variable

  1. #1
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    Aug 2005
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    2

    Calling functions via variable

    Ok, teaching myself C++ at the moment and have learned enought to get a text-based something or other going

    Anyway, Im going to issue this game commands via the console. I have already gotten them to uppercase for recognition, but now I cant seem to call my functions.

    I input my command:

    Code:
    cin >> command;
    Then I convert it:

    Code:
    for (int i = 0; i < command.size(); i++)//make the command uppercase
            {
                command[i] = toupper(command[i]);
            }
    Then I try to call my function(s), which are all defined.

    Code:
    command();
    The error: no match to call to '(std::string)'
    IDE: Bloodshed Dev C++


    I tried using the '*' for reference but still doesnt work, even though I still dont fully understand the use of the asterisk...

    Anway, Is there a simple way to get what I want done?

  2. #2
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    The simplest way would be to use a series of if, else if statements that compare the command string to a built-in string and then executes the proper function if they match.
    Code:
    if (command == "run")
      run();
    else if (command == "hide")
      hide();
    // etc.
    There are also more advanced ways like mapping the string to a function pointer.
    Last edited by Daved; 08-30-2005 at 09:38 PM.

  3. #3
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    The 20 or so IF's was what I was trying to avoid, case select would work too, was trying to take the easy way

  4. #4
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    >> case select would work too
    Not with strings, only with integers or chars.

    The map version is actually not that hard, especially if your functions all have the same signature.

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