xo-alloc/xo-tokenizer/example/tokenrepl/tokenrepl.cpp

77 lines
1.9 KiB
C++

/** @file tokenrepl.cpp **/
#include "xo/tokenizer/tokenizer.hpp"
#include <iostream>
#include <unistd.h> // for isatty
bool repl_getline(bool interactive, std::istream& in, std::ostream& out, std::string& input)
{
if (interactive) {
out << "> ";
std::flush(out);
}
return static_cast<bool>(std::getline(in, input));
}
int
main() {
using namespace xo::scm;
using namespace std;
using tokenizer_type = tokenizer<char>;
using span_type = tokenizer_type::span_type;
xo::log_config::min_log_level = xo::log_level::info;
bool interactive = isatty(STDIN_FILENO);
tokenizer_type tkz(xo::log_config::min_log_level <= xo::log_level::info);
string input_str;
while (repl_getline(interactive, cin, cout, input_str)) {
// we want tokenizer to see newline, it's syntax
input_str.push_back('\n');
span_type input = span_type::from_string(input_str);
// reminder: input may contain multiple tokens
while (!input.empty()) {
auto [tk, consumed, error] = tkz.scan(input);
if (tk.is_valid()) {
cout << tk << endl;
} else if (error.is_error()) {
cout << "parsing error: " << endl;
error.report(cout);
break;
}
input = tkz.consume(consumed, input);
}
/* here: input.empty() or error encountered */
/* discard stashed remainder of input line
* (for nicely-formatted errors)
*/
tkz.discard_current_line();
}
{
span_type input = span_type::from_string(input_str);
auto [tk, consumed, error] = tkz.notify_eof(input);
input = tkz.consume(consumed, input);
if (tk.is_valid()) {
cout << tk << endl;
} else if (error.is_error()) {
cout << "parsing error: " << endl;
error.report(cout);
}
}
}
/** end tokenrepl.cpp */