g ++坏了吗？(g++ broken? Cannot add new methods to class [closed])

g ++坏了吗？(g++ broken? Cannot add new methods to class [closed])

我正在创建一个符号表类，用于我为编译器课程编写的分析器/解析器。 到目前为止，一切进展顺利，但我无法使用g ++在我学校的Linux机器上编译这些类文件：

SymbolTable.h：

// Multiple definition guard #ifndef SYMBOLTABLE_H #defineSYMBOLTABLE_H // Includes #include <iostream> #include <string> #include "stddef.h" // Namespace using namespace std; // Class for storing all encountered symbols while parsing class SymbolTable { public: SymbolTable(); // Constructor ~SymbolTable(); // Destructor void scopeUp(); // Increases current scope void scopeDown(); // Decreases current scope void addSymbol(string symbolTitle); // Adds a symbol to table void addSymboll(string symbolTitle); // g++ doesn't think this exists private: int scope; // Structure for storing symbols. Currently only contains title from // identifier. Will expand upon / derive from this structure after // initial testing. Symbols are stored in a simple stack, with the // container class responsible for keeping track of the top Symbol. struct Symbol { Symbol* previousSymbol; string title; }; // Structure for tracking current scope. All symbols will belong to a // particular scope, and are stored in a simple stack to maintain // declaration order. When the scope changes, currentScope will point to // a new scope structure with its own list of symbols. Scopes themselves // are also stored in a stack, where currentScope points to the top. struct Scope { Scope* previousScope; Symbol* currentSymbol; }; Scope* currentScope; // This is a recursive display function used for printing all of the items // in a given scope. This is called from within the scopeDown function, so // that the final list of items for that scope can be logged before it is // destroyed void displayScope(Symbol* displaySymbol); }; #endif // Multiple definition guard

SymbolTable.cpp：

// Multiple definition guard #ifndef SYMBOLTABLE_CPP #define SYMBOLTABLE_CPP // Includes #include "SymbolTable.h" // Constructor SymbolTable::SymbolTable() { scope = 0; currentScope = NULL; return; } // Destructor SymbolTable::~SymbolTable() { Scope* nextScopeToDelete = NULL; Symbol* nextSymbolToDelete = NULL; // While there are scopes left to delete from the table... while(currentScope != NULL) { // Save the pointer to the next scope on the stack nextScopeToDelete = currentScope->previousScope; // While there are symbols left to delete from the scope... while(currentScope->currentSymbol != NULL) { // Save the pointer to the next symbol on the stack nextSymbolToDelete = currentScope->currentSymbol->previousSymbol; // For debugging cout << "deleting symbol " << currentScope->currentSymbol->title << endl; // Delete the current top symbol delete currentScope->currentSymbol; // Move on to the next one currentScope->currentSymbol = nextSymbolToDelete; } // For debugging cout << "deleting scope " << scope << endl; // Delete the current top scope delete currentScope; scope--; // Move on to the next one currentScope = nextScopeToDelete; } return; } // This is a recursive display function used for printing all of the items // in a given scope. This is called from within the scopeDown function, so // that the final list of items for that scope can be logged before it is // destroyed void SymbolTable::displayScope(Symbol* displaySymbol) { // If we've reached the bottom of the scope stack... if(displaySymbol == NULL) { return; // Nothing to do } // We haven't reached the bottom of the scope stack else { displaySymbol = displaySymbol->previousSymbol; // Keep going displayScope(displaySymbol); // Recursive call } // Display this symbol after all lower ones have been displayed recursively cout << displaySymbol->title << endl; return; } // A new procedure has caused us to increase scope, so we'll create a new // scope structure with its own symbol stack void SymbolTable::scopeUp() { // Generate the new scope structure Scope* newScope = new Scope; newScope->previousScope = currentScope; newScope->currentSymbol = NULL; // Notification for debugging cout << "ENTERING SCOPE " << scope + 1 << endl; cout << "--------------------------------------------------"; cout << "-------------------------" << endl; // Switch to the new scope currentScope = newScope; scope++; return; } // The end of a procedure has caused us to decrement scope, so we'll delete // the contents of the current one and fall back to the last scope on the stack void SymbolTable::scopeDown() { // If we're already at the bottom of the stack... if(currentScope == 0) { // Something is very wrong cerr << "CANNOT DELETE SCOPE 0!!!!" << endl; } else { // Save the pointer to the next scope on the stack Scope* previousScope = currentScope->previousScope; Symbol* nextSymbolToDelete = NULL; // Display the contents of this scope before deleting it (debugging) displayScope(currentScope->currentSymbol); // While there are still symbols in this scope to delete... while(currentScope->currentSymbol != NULL) { // Save the pointer to the next symbol on the stack nextSymbolToDelete = currentScope->currentSymbol->previousSymbol; // Delete the current top symbol on the stack delete currentScope->currentSymbol; // Move on to the next one currentScope->currentSymbol = nextSymbolToDelete; } // Notification for debugging cout << "EXITING SCOPE " << scope-- << endl; cout << "=================================================="; cout << "=========================" << endl; // Delete the old top scope from the stack delete currentScope; // Move on to the next one currentScope = previousScope; } return; } // Adds a symbol to the table. Specifically: adds a symbol to the top of the // symbol stack in the scope at the top of the scope stack. This will soon be // interfacing with more expansive data structure, but currently just stores // the title of the symbol as detected in the parser. void SymbolTable::addSymbol(string symbolTitle) { Symbol* newSymbol = new Symbol; newSymbol->previousSymbol = currentScope->currentSymbol; newSymbol->title = symbolTitle; currentScope->currentSymbol = newSymbol; return; } // g++ doesn't think this was declared in the class void SymbolTable::addSymboll(string symbolTitle) { Symbol* newSymbol = new Symbol; newSymbol->previousSymbol = currentScope->currentSymbol; newSymbol->title = symbolTitle; currentScope->currentSymbol = newSymbol; return; } #endif // Multiple definition guard

错误：

[...]$ touch SymbolTable.h SymbolTable.cpp [...]$ g++ -c SymbolTable.cpp SymbolTable.cpp:67: error: no âvoid SymbolTable::displayScope(SymbolTable::Symbol*)â member function declared in class âSymbolTableâ SymbolTable.cpp:167: error: no âvoid SymbolTable::addSymboll(std::string)â member function declared in class âSymbolTableâ [...]$

据我所知，它似乎认为我的displayScope函数没有在类头文件中声明。 为了进一步研究这个问题，我添加了一个名为addSymboll的新函数，它与现有的addSymbol函数相同。 但是，它为这个新功能提供了相同的错误消息。 事实上，在花了几个小时试图编译之后，似乎我根本无法向这个类添加任何新函数。 关于造成这种情况的原因，我完全不知所措。 任何想法，将不胜感激！

I am creating a symbol table class to be used with an analyzer/parser I've written for a compilers course. Everything has been going well so far, but I cannot get these class files to compile on my school's Linux machines using g++:

SymbolTable.h:

// Multiple definition guard #ifndef SYMBOLTABLE_H #defineSYMBOLTABLE_H // Includes #include <iostream> #include <string> #include "stddef.h" // Namespace using namespace std; // Class for storing all encountered symbols while parsing class SymbolTable { public: SymbolTable(); // Constructor ~SymbolTable(); // Destructor void scopeUp(); // Increases current scope void scopeDown(); // Decreases current scope void addSymbol(string symbolTitle); // Adds a symbol to table void addSymboll(string symbolTitle); // g++ doesn't think this exists private: int scope; // Structure for storing symbols. Currently only contains title from // identifier. Will expand upon / derive from this structure after // initial testing. Symbols are stored in a simple stack, with the // container class responsible for keeping track of the top Symbol. struct Symbol { Symbol* previousSymbol; string title; }; // Structure for tracking current scope. All symbols will belong to a // particular scope, and are stored in a simple stack to maintain // declaration order. When the scope changes, currentScope will point to // a new scope structure with its own list of symbols. Scopes themselves // are also stored in a stack, where currentScope points to the top. struct Scope { Scope* previousScope; Symbol* currentSymbol; }; Scope* currentScope; // This is a recursive display function used for printing all of the items // in a given scope. This is called from within the scopeDown function, so // that the final list of items for that scope can be logged before it is // destroyed void displayScope(Symbol* displaySymbol); }; #endif // Multiple definition guard

SymbolTable.cpp:

// Multiple definition guard #ifndef SYMBOLTABLE_CPP #define SYMBOLTABLE_CPP // Includes #include "SymbolTable.h" // Constructor SymbolTable::SymbolTable() { scope = 0; currentScope = NULL; return; } // Destructor SymbolTable::~SymbolTable() { Scope* nextScopeToDelete = NULL; Symbol* nextSymbolToDelete = NULL; // While there are scopes left to delete from the table... while(currentScope != NULL) { // Save the pointer to the next scope on the stack nextScopeToDelete = currentScope->previousScope; // While there are symbols left to delete from the scope... while(currentScope->currentSymbol != NULL) { // Save the pointer to the next symbol on the stack nextSymbolToDelete = currentScope->currentSymbol->previousSymbol; // For debugging cout << "deleting symbol " << currentScope->currentSymbol->title << endl; // Delete the current top symbol delete currentScope->currentSymbol; // Move on to the next one currentScope->currentSymbol = nextSymbolToDelete; } // For debugging cout << "deleting scope " << scope << endl; // Delete the current top scope delete currentScope; scope--; // Move on to the next one currentScope = nextScopeToDelete; } return; } // This is a recursive display function used for printing all of the items // in a given scope. This is called from within the scopeDown function, so // that the final list of items for that scope can be logged before it is // destroyed void SymbolTable::displayScope(Symbol* displaySymbol) { // If we've reached the bottom of the scope stack... if(displaySymbol == NULL) { return; // Nothing to do } // We haven't reached the bottom of the scope stack else { displaySymbol = displaySymbol->previousSymbol; // Keep going displayScope(displaySymbol); // Recursive call } // Display this symbol after all lower ones have been displayed recursively cout << displaySymbol->title << endl; return; } // A new procedure has caused us to increase scope, so we'll create a new // scope structure with its own symbol stack void SymbolTable::scopeUp() { // Generate the new scope structure Scope* newScope = new Scope; newScope->previousScope = currentScope; newScope->currentSymbol = NULL; // Notification for debugging cout << "ENTERING SCOPE " << scope + 1 << endl; cout << "--------------------------------------------------"; cout << "-------------------------" << endl; // Switch to the new scope currentScope = newScope; scope++; return; } // The end of a procedure has caused us to decrement scope, so we'll delete // the contents of the current one and fall back to the last scope on the stack void SymbolTable::scopeDown() { // If we're already at the bottom of the stack... if(currentScope == 0) { // Something is very wrong cerr << "CANNOT DELETE SCOPE 0!!!!" << endl; } else { // Save the pointer to the next scope on the stack Scope* previousScope = currentScope->previousScope; Symbol* nextSymbolToDelete = NULL; // Display the contents of this scope before deleting it (debugging) displayScope(currentScope->currentSymbol); // While there are still symbols in this scope to delete... while(currentScope->currentSymbol != NULL) { // Save the pointer to the next symbol on the stack nextSymbolToDelete = currentScope->currentSymbol->previousSymbol; // Delete the current top symbol on the stack delete currentScope->currentSymbol; // Move on to the next one currentScope->currentSymbol = nextSymbolToDelete; } // Notification for debugging cout << "EXITING SCOPE " << scope-- << endl; cout << "=================================================="; cout << "=========================" << endl; // Delete the old top scope from the stack delete currentScope; // Move on to the next one currentScope = previousScope; } return; } // Adds a symbol to the table. Specifically: adds a symbol to the top of the // symbol stack in the scope at the top of the scope stack. This will soon be // interfacing with more expansive data structure, but currently just stores // the title of the symbol as detected in the parser. void SymbolTable::addSymbol(string symbolTitle) { Symbol* newSymbol = new Symbol; newSymbol->previousSymbol = currentScope->currentSymbol; newSymbol->title = symbolTitle; currentScope->currentSymbol = newSymbol; return; } // g++ doesn't think this was declared in the class void SymbolTable::addSymboll(string symbolTitle) { Symbol* newSymbol = new Symbol; newSymbol->previousSymbol = currentScope->currentSymbol; newSymbol->title = symbolTitle; currentScope->currentSymbol = newSymbol; return; } #endif // Multiple definition guard

Errors:

[...]$ touch SymbolTable.h SymbolTable.cpp [...]$ g++ -c SymbolTable.cpp SymbolTable.cpp:67: error: no âvoid SymbolTable::displayScope(SymbolTable::Symbol*)â member function declared in class âSymbolTableâ SymbolTable.cpp:167: error: no âvoid SymbolTable::addSymboll(std::string)â member function declared in class âSymbolTableâ [...]$

As far as I can tell, it seemed to think my displayScope function was not declared in the class header file. In order to investigate this further, I added a new function called addSymboll which was identical to the existing addSymbol function. However, it's giving me the same error message for this new function. In fact, after a couple of hours spent trying to compile this, it seems that I cannot add any new functions to this class at all. I am at a complete loss as to what could be causing this. Any ideas would be appreciated!

最满意答案

G ++还告诉我：

错误：无效的预处理指令#defineSYMBOLTABLE_H

在#define之后添加一个空格：

#defineSYMBOLTABLE_H

I had previously only been deleting the object (.o) files when cleaning. What I ended up having to do here was delete the .gch files as well. There was nothing wrong with the actual code or g++ (despite the old version running on the school servers).