我是一名 Scheme 程序员，我正在尝试使用 Guile 从 Bison 规范中的 C++ 代码调用 Scheme 函数。关于 Guile 和 C 的文档很棒；但是，我还没有找到很多有关 Guile 和 C++ 的最新信息。因为每个 C 程序在技术上都是 C++ 程序，所以通过 Guile 从 C++ 调用 Scheme 函数应该很容易。唉，我不是 C/C++ 程序员，所以我希望这里的一些 C++ 大师可以帮助我。这是我的一些代码：
%{
#include <fstream>
#include <iomanip>
#include <string>
using namespace std;
#include "List.h"
#include "paslex.h"
#include "paspar.h"
#include <libguile.h>
extern "C" {
#include "symtable.h"
}
void yyerror(char* m);
extern ofstream tfs;
extern int line;
extern int col;
extern "C" {
// Create namespace stack and lexical level 0 with built-in types.
SCM namespace_stack;
SCM namespace0;
SCM real_type;
SCM real_type_sym;
SCM integer_type;
SCM integer_type_sym;
// errors begin here
namespace_stack = make_name_stack();
namespace0 = make_namespace();
real_type = make_type_attr(64, 64);
real_type_sym = make_type_sym("real", real_type);
integer_type = make_type_attr(32, 32);
integer_type_sym = make_type_sym("integer", integer_type);
insert_symbol(real_type_sym, namespace0);
insert_symbol(integer_type_sym, namespace0);
push(namespace0, namespace_stack);
}
%}
我的 Scheme 代码的包装函数在 symtable.c 中。在纯 C 中使用这些相同的函数就可以了。从 C++ 调用它们会产生以下编译器错误：
paspar.y:33: 错误: '=' 标记之前的预期构造函数、析构函数或类型转换
...以及第 34 行到第 42 行的类似错误。我在 Ubuntu 10.10 上使用 GCC 4.4.5 和 Guile 1.6.8。我尝试将 libguile.h 包含在 extern "C" 块的内部和外部，但结果是一样的。我确定这是一个新手错误，但非常感谢您对这个问题的帮助。如果需要更多信息，请告诉我。我在下面包含了 symtable.h：
// Description: API to translator symbol table, including namespaces,
// namespace stacks, and descriptors.
// Constants used by descriptors.
#define CONSTANT_ID 0
#define FUNCTION_ID 1
#define PROCEDURE_ID 2
#define VARIABLE_ID 3
#define TYPE_SYM_ID 4
#define TYPE_ATTR_ID 5
#define TYPE_ENUM_ID 6
#define TYPE_RANGE_ID 7
#define TYPE_ARRAY_ID 8
#define TYPE_RECORD_ID 9
#define TYPE_POINTER_ID 10
#define TYPE_SET_ID 11
//------------------------------------NAMESPACE STACK--------------------------------------
SCM make_name_stack();
// Create and return a namespace stack.
void push(SCM namspace, SCM stack);
// Places a namespace on the stack.
// @param stack The stack to place value on.
// @param namspace The namespace to place on the stack.
// @return None
SCM pop(SCM stack);
// Returns namespace on top of stack.
// @param stack The stack to return value from.
// @return The namespace on top of stack.
void sremove(SCM stack);
// Removes the top value on stack.
// @param stack The stack to remove top value from.
// @return None
int empty(SCM stack);
// A predicate for determining if a stack is empty.
// @param Stack The stack to test.
// @return 1 if the stack is empty, 0 if it is not.
SCM find_stack_symbol(char* name, SCM stack);
// Finds the symbol descriptor for the given identifier.
// @param name The symbol name.
// @param stack The stack to search.
// @return The symbol descriptor or 0 if the symbol could not be found.
int lexical_level(char* name, SCM stack);
// Find the lexical level of the identifier.
// @param name The symbol name.
// @param stack The stack to search.
// @return The lexical level or -1 if the symbol could not be found.
int current_level(SCM stack);
// Find lexical level of the top namespace.
// @param stack The stack to search.
// @return The lexical level or -1 if stack is empty.
//------------------------------------NAMESPACE--------------------------------------
SCM make_namespace();
// Create and return a namespace.
void insert_symbol(SCM symbol, SCM namspace);
// Insert descriptor into namespace
// @param descriptor The descriptor to insert.
// @param namspace The namespace to insert the descriptor into.
// @return Nothing.
SCM find_symbol(SCM symbol, SCM namspace);
// Search for symbol in target namespace.
// @param symbol The symbol to search for.
// @param namspace The namespace to search for symbol.
// @return A symbol descriptor, or 0 if symbol not found.
int get_lex(SCM namspace);
// Get lexical level of target namespace.
// @param namspace The namespace whose lexical level to get.
// @return Lexical level, or -1 if namespace has not yet been assigned one.
// ------------------------------SYMBOL DESCRIPTORS-------------------------------
SCM make_constant(char* name, SCM type, char* value);
// Makes a constant symbol descriptor.
// @param identifier Name of the constant.
// @param type The constant's type descriptor.
// @param value String representation of the constant.
// @return A constant symbol descriptor.
SCM make_var(char* name, SCM type, double address);
// Makes a variable symbol descriptor.
// @param identifier Name of the variable.
// @param type Address of the variable's type descriptor.
// @param address Starting address of the variable itself.
// @return A variable symbol descriptor.
SCM make_function(char* name, SCM params, double address);
// Makes a function symbol descriptor.
// @param identifier Name of the function.
// @param params A list of function parameters. The first element should
// always be the return type.
// @param address Address of the first function instruction.
// @return A function symbol descriptor.
SCM make_procedure(char* name, SCM params, double address);
// Makes a procedure symbol descriptor.
// @param identifier Name of the procedure.
// @param params A list of procedure parameters. Does not include a return type.
// @param address Address of the first procedure instruction.
// @return A procedure symbol descriptor.
SCM make_type_sym(char* name, SCM type);
// Make a type symbol descriptor.
// @param identifer Name of the type.
// @param type Address of the type's attributes.
// @return A type symbol descriptor.
int get_id(SCM descriptor);
// Return descriptor id.
void get_name(SCM descriptor, char* name);
// Return descriptor name.
// @param descriptor Target descriptor.
// @param name Output parameter for descriptor name.
int get_value(SCM descriptor, char* value);
// Get string representation of a constant symbol descriptor.
// @param descriptor Target descriptor.
// @param value Output parameter for descriptor value.
// @return 0 if not a constant, 1 if a constant.
double get_address(SCM descriptor);
// Get address of descriptor.
// @param descriptor Target descriptor.
// @return address, or -1 if descriptor does not possess an address.
SCM get_params(SCM descriptor);
// Get parameter list of descriptor.
// @param descriptor Target descriptor.
// @return parameter list, or 0 if descriptor does not possess a parameter list.
SCM get_type(SCM descriptor);
// Get type referenced by descriptor.
// @param descriptor Target descriptor.
// @return type, or 0 if descriptor does not reference a type.
int set_type(SCM descriptor, SCM type);
// Set type referenced by descriptor.
// @param descriptor Target descriptor.
// @param type Target type.
// @return 1 if type set successfully, or 0 if it failed.
// -------------------------------TYPE DESCRIPTORS-------------------------------
SCM make_type_attr(double size, int align);
// Make a type symbol attribute descriptor.
// @param size Size of the type in bits.
// @param align Type alignment in bits.
// @return A type attribute descriptor.
SCM make_type_enum(double size, int align, SCM syms);
// Make an enumerated type descriptor.
// @param size Size of the type in bits.
// @param align Alignment of the type in bits.
// @param syms A Scheme list of symbol type descriptors.
// @return An enumerated type descriptor.
SCM make_type_range(double size, int align, SCM low, SCM high);
// Make a ranged type.
// @param size Size of the type in bits.
// @param align Alignment of the type in bits.
// @param low Low value in the range (a symbol descriptor).
// @param high High value in the range (a symbol descriptor).
// @return A ranged type descriptor.
SCM make_type_array(double size, int align, SCM index, SCM element);
// Make an array type.
// @param size Size of the type in bits.
// @param align Alignment of the type in bits.
// @param index The type of allowable index values (a symbol descriptor).
// @param element The type of allowable element values (a symbol descriptor).
// @return An array type descriptor.
SCM make_type_record(double size, int align, SCM vars);
// Make a record type.
// @param size Size of the type in bits.
// @param align Alignment of the type in bits.
// @param vars A Scheme list of variable type descriptors.
// @return A record type descriptor.
SCM make_type_pointer(double size, int align, SCM type);
// Make a pointer type.
// @param size Size of the type in bits.
// @param align Alignment of the type in bits.
// @param type The type pointer is referencing.
// @return A pointer type.
SCM make_type_set(double size, int align, SCM enum_type);
// Make a set type.
// @param size Size of the type in bits.
// @param align Alignment of the type in bits.
// @param enum The enumerated type used by this set.
// @return A set type.
SCM make_type_null();
// Make a null type for use when the descriptor type is not known
// at creation time.
int check_null(SCM type);
// Checks if a type is null.
// Returns 1 if null, or 0 if not null.
double get_size(SCM descriptor);
// Return size of type in bits.
int get_align(SCM descriptor);
// Return alignment of type in bits.
SCM get_vars(SCM descriptor, int* boolean);
// Return variable list from record descriptor.
// @param descriptor Target descriptor.
// @param boolean Output parameter returns 0 if not record descriptor.
// @return A variable list.
SCM get_index(SCM descriptor, int* boolean);
// Return index type from array descriptor.
// @param descriptor Target descriptor.
// @param boolean Output parameter returns 0 if not array descriptor.
// @return Index type.
SCM get_element(SCM descriptor, int* boolean);
// Return element type from array descriptor.
// @param descriptor Target descriptor.
// @param boolean Output parameter returns 0 if not array descriptor.
// @return Element type.
SCM get_low(SCM descriptor, int* boolean);
// Return low type from range descriptor.
// @param descriptor Target descriptor.
// @param boolean Output parameter returns 0 if not range descriptor.
// @return Low type.
SCM get_high(SCM descriptor, int* boolean);
// Return high type from range descriptor.
// @param descriptor Target descriptor.
// @param boolean Output parameter returns 0 if not range descriptor.
// @return High type.
SCM get_syms(SCM descriptor, int* boolean);
// Return symbol list from enumerated descriptor.
// @param descriptor Target descriptor.
// @param boolean Output parameter returns 0 if not enumerated descriptor.
// @return Symbol list.