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#pragma once
#include <iostream>
#include <vector>
#include <cassert>
namespace nix {
void toJSON(std::ostream & str, const char * start, const char * end);
void toJSON(std::ostream & str, const char * s);
template<typename T>
void toJSON(std::ostream & str, const T & n);
class JSONWriter
{
protected:
struct JSONState
{
std::ostream & str;
bool indent;
size_t depth = 0;
std::vector<JSONWriter *> stack;
JSONState(std::ostream & str, bool indent) : str(str), indent(indent) { }
~JSONState()
{
assert(stack.empty());
}
};
JSONState * state;
bool first = true;
JSONWriter(std::ostream & str, bool indent);
JSONWriter(JSONState * state);
~JSONWriter();
void assertActive()
{
assert(!state->stack.empty() && state->stack.back() == this);
}
void comma();
void indent();
};
class JSONObject;
class JSONPlaceholder;
class JSONList : JSONWriter
{
private:
friend class JSONObject;
friend class JSONPlaceholder;
void open();
JSONList(JSONState * state)
: JSONWriter(state)
{
open();
}
public:
JSONList(std::ostream & str, bool indent = false)
: JSONWriter(str, indent)
{
open();
}
~JSONList();
template<typename T>
JSONList & elem(const T & v)
{
comma();
toJSON(state->str, v);
return *this;
}
JSONList list();
JSONObject object();
JSONPlaceholder placeholder();
};
class JSONObject : JSONWriter
{
private:
friend class JSONList;
friend class JSONPlaceholder;
void open();
JSONObject(JSONState * state)
: JSONWriter(state)
{
open();
}
void attr(const std::string & s);
public:
JSONObject(std::ostream & str, bool indent = false)
: JSONWriter(str, indent)
{
open();
}
~JSONObject();
template<typename T>
JSONObject & attr(const std::string & name, const T & v)
{
attr(name);
toJSON(state->str, v);
return *this;
}
JSONList list(const std::string & name);
JSONObject object(const std::string & name);
JSONPlaceholder placeholder(const std::string & name);
};
class JSONPlaceholder : JSONWriter
{
private:
friend class JSONList;
friend class JSONObject;
JSONPlaceholder(JSONState * state)
: JSONWriter(state)
{
}
void assertValid()
{
assertActive();
assert(first);
}
public:
JSONPlaceholder(std::ostream & str, bool indent = false)
: JSONWriter(str, indent)
{
}
~JSONPlaceholder()
{
assert(!first || std::uncaught_exception());
}
template<typename T>
void write(const T & v)
{
assertValid();
first = false;
toJSON(state->str, v);
}
JSONList list();
JSONObject object();
};
}
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