c++ - 在 C++ 中调用函数是不明确的。候选函数是原型(prototype)和函数本身

Question

我正在完成 Stanford CS106B C++ 作业，但作业存在“语义问题”。

编译器似乎无法推断调用是针对函数还是函数原型(prototype)。我不明白为什么会调用原型(prototype)。我怎样才能做到调用函数而不是原型(prototype)？我收到的错误消息是“调用‘humansTurn’不明确”。

错误消息与页面底部 humanTurn(Lexicon,Lexicon) 函数内的 humanTurn(Lexicon,Lexicon) 函数的调用有关。该函数的原型(prototype)在主函数之上。

如有任何帮助，我们将不胜感激。

亲切的问候，

梅胡尔

    /*
     * File: Boggle.cpp
     * ----------------
     */

    #include <iostream>
    #include "gboggle.h"
    #include "graphics.h"
    #include "grid.h"
    #include "vector.h"
    #include "lexicon.h"
    #include "random.h"
    #include "simpio.h"
    using namespace std;

    /* Constants */

    const int BOGGLE_WINDOW_WIDTH = 650;
    const int BOGGLE_WINDOW_HEIGHT = 350;

    const string STANDARD_CUBES[16]  = {
       "AAEEGN", "ABBJOO", "ACHOPS", "AFFKPS",
       "AOOTTW", "CIMOTU", "DEILRX", "DELRVY",
       "DISTTY", "EEGHNW", "EEINSU", "EHRTVW",
       "EIOSST", "ELRTTY", "HIMNQU", "HLNNRZ"
    };

    const string BIG_BOGGLE_CUBES[25]  = {
       "AAAFRS", "AAEEEE", "AAFIRS", "ADENNN", "AEEEEM",
       "AEEGMU", "AEGMNN", "AFIRSY", "BJKQXZ", "CCNSTW",
       "CEIILT", "CEILPT", "CEIPST", "DDLNOR", "DDHNOT",
       "DHHLOR", "DHLNOR", "EIIITT", "EMOTTT", "ENSSSU",
       "FIPRSY", "GORRVW", "HIPRRY", "NOOTUW", "OOOTTU"
    };

    /* Function prototypes */

    void welcome();
    void giveInstructions();
    // Create random board
    static Grid <char> randomBoard();
    // Create custom board
    static Grid<char> customBoard();
    static void drawAndFillBoard(Grid<char>);
    static void humansTurn(Lexicon,Lexicon);

    int main() {
        initGraphics(BOGGLE_WINDOW_WIDTH, BOGGLE_WINDOW_HEIGHT);
        welcome();
        giveInstructions();
        string custom = getLine("Type y to create custom board:" );
        Grid<char> gridData;
        if (custom=="y"){
            gridData = customBoard();
        } else {
            gridData = randomBoard();
            }
        drawAndFillBoard(gridData);
        Lexicon english("EnglishWords.dat");
        // Lexicon holds words previously encountered
        Lexicon previousWords;
        humansTurn(english, previousWords);
        return 0;
    }

    /*
     * Function: welcome
     * Usage: welcome();
     * -----------------
     * Print out a cheery welcome message.
     */

    void welcome() {
       cout << "Welcome!  You're about to play an intense game " << endl;
    }

    /*
     * Function: giveInstructions
     * Usage: giveInstructions();
     * --------------------------
     * Print out the instructions for the user.
     */

    void giveInstructions() {
       cout << endl;
       cout << "The boggle board is a grid onto which I ";
       cout << "or triple your paltry score." << endl << endl;
       cout << "Hit return when you're ready...";
       getLine();
    }

    static Grid<char> randomBoard(){
        Vector<string> standardCubes;
        for(int i = 0; i<16;i++){
            standardCubes.add(STANDARD_CUBES[i]);
        }
        // Shuffle cubes
        for (int i = 0; i < standardCubes.size(); i++) {
            int r = randomInteger(i, standardCubes.size()-1);
            if (i!=r){
                string stringToMove1 = standardCubes.get(i);
                string stringToMove2 = standardCubes.get(r);
                standardCubes.set(r, stringToMove1);
                standardCubes.set(i, stringToMove2);
            }
        }
        // Update grid with random side of cube
        Grid<char> gridData(4, 4);
        int counter = 0;
        for (int columnNo = 0; columnNo <4; columnNo++){
            for (int rowNo = 0; rowNo<4; rowNo++) {
                string s = standardCubes.get(counter);
                int r = randomInteger(0, 5);
                gridData[columnNo][rowNo] = s[r];
                counter++;
            }
        }
        return gridData;
    }

    static Grid<char> customBoard(){
        Grid<char> gridData(4,4);
        string s = getLine("Please enter 16 characters to make up the custom board. Characters will fill the board left to right, top to bottom: ");
        for (int i = 0; i < s.length(); i++) {
            s[i] = toupper(s[i]);
        }
        if (s.length()<16){
            cout << "String has to be 16 characters long, try again" << endl;
            customBoard();
        }
        int i =0;
        for (int columnNo = 0; columnNo <4; columnNo++){
            for (int rowNo = 0; rowNo<4; rowNo++) {
                gridData[columnNo][rowNo] = s[i];
                i++;
            }
        }

        return gridData;
    }

    static void drawAndFillBoard(Grid<char> gridData){
        drawBoard(4, 4);
        for (int columnNo = 0; columnNo <4; columnNo++){
            for (int rowNo = 0; rowNo<4; rowNo++) {
                labelCube(rowNo, columnNo, gridData[rowNo][columnNo]);
            }
        }
    }

    static void humansTurn(Lexicon englishWords, Lexicon &previousWords){
        /*
         Human’s turn (except for finding words on the board). Write the loop that allows the user to enter words. Reject words that have already been entered or that don’t meet the minimum word length or that aren’t in the lexicon. Use the gboggle functions to add words to the graphical display and keep score.
         */

        string humanGuess = getLine("Please enter your guess: ");
        for (int i = 0; i < humanGuess.length(); i++) {
            humanGuess[i] = tolower(humanGuess[i]);
        }
        if (humanGuess.length()<4){
            cout << "Min guess length is four characters" << endl;
            humansTurn(englishWords, previousWords);
        }
        if (!englishWords.contains(humanGuess)) {
            cout << "That word is not English, please try another word" << endl;
            humansTurn(englishWords, previousWords);
        }
        if (previousWords.contains(humanGuess)){
            cout << "That word has already been guessed, please try another word" << endl;
            humansTurn(englishWords, previousWords);
        }
        // check if word can be made using data on board

    }

Answer 1

您的函数 humanTurn 定义具有与声明不同的签名

函数声明:

static void humansTurn(Lexicon,Lexicon);

函数定义:

static void humansTurn(Lexicon englishWords, Lexicon &previousWords) 
                                                     ^^
                                                     //Here