You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
alee-forth/alee.cpp

136 lines
3.4 KiB
C++

/**
* Alee Forth: A portable and concise Forth implementation in modern C++.
* Copyright (C) 2023 Clyne Sullivan <clyne@bitgloo.com>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
#include "alee.hpp"
#include "memdict.hpp"
#include <fstream>
#include <iostream>
#include <vector>
static bool okay = false;
static void readchar(State& state);
static void parseLine(Parser&, State&, std::string_view);
static void parseFile(Parser&, State&, std::istream&);
int main(int argc, char *argv[])
{
MemDict dict;
State state (dict, readchar);
Parser parser;
dict.write(Dictionary::Base, 10);
dict.write(Dictionary::Latest, Dictionary::Begin);
dict.write(Dictionary::Compiling, 0);
dict.write(Dictionary::Postpone, 0);
std::vector args (argv + 1, argv + argc);
for (const auto& a : args) {
std::ifstream file (a);
parseFile(parser, state, file);
}
okay = true;
parseFile(parser, state, std::cin);
return 0;
}
static void readchar(State& state)
{
auto len = state.dict.read(Dictionary::Input);
Addr addr = Dictionary::Input + sizeof(Cell) +
Dictionary::InputCells - len - 1;
for (Addr i = 0; i < len; ++i, ++addr)
state.dict.writebyte(addr, state.dict.readbyte(addr + 1));
auto c = std::cin.get();
state.dict.writebyte(addr, c ? c : ' ');
state.dict.write(Dictionary::Input, len + 1);
}
static void save(State& state)
{
std::ofstream file ("alee.dat", std::ios::binary);
if (file.good()) {
for (Addr i = 0; i < state.dict.here; ++i)
file.put(state.dict.readbyte(i));
}
}
static void load(State& state)
{
std::ifstream file ("alee.dat", std::ios::binary);
Addr i = 0;
while (file.good())
state.dict.writebyte(i++, file.get());
state.dict.here = i - 1;
}
void user_sys(State& state)
{
switch (state.pop()) {
case 0:
std::cout << state.pop() << ' ';
break;
case 1:
std::cout << static_cast<char>(state.pop());
break;
case 2:
save(state);
break;
case 3:
load(state);
break;
}
}
void parseLine(Parser& parser, State& state, std::string_view line)
{
if (auto r = parser.parse(state, line); r == 0) {
if (okay)
std::cout << (state.compiling() ? "compiled" : "ok") << std::endl;
} else {
switch (r) {
case Parser::UnknownWord:
std::cout << "word not found in: " << line << std::endl;
break;
default:
break;
}
}
}
void parseFile(Parser& parser, State& state, std::istream& file)
{
while (file.good()) {
std::string line;
std::getline(file, line);
if (line == "bye")
exit(0);
parseLine(parser, state, line);
}
}