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#include "model.h"
#include "builtin.h"
#include "parser.h"
#include "eval.h"
#include "exc.h"
#include "gc.h"
#include <cstdio>
#include <cstdlib>
GarbageCollector gc;
Tokenizor tk;
ASTGenerator ast;
Evaluator eval;
void load_file(const char *fname) {
FILE *f = fopen(fname, "r");
if (!f)
{
printf("Can not open file: %s\n", fname);
exit(0);
}
tk.set_stream(f);
Pair *tree;
while (1)
{
try
{
tree = ast.absorb(&tk);
if (!tree) break;
EvalObj *ret = eval.run_expr(tree);
gc.expose(ret);
}
catch (GeneralError &e)
{
fprintf(stderr, "An error occured: %s\n", e.get_msg().c_str());
}
gc.collect();
}
}
void print_help(const char *cmd) {
fprintf(stderr,
"Sonsi: Stupid and Obvious Scheme Interpreter\n"
"Usage: %s OPTION ...\n"
"Evaluate Scheme code, interactively or from a script.\n\n"
" FILE \t\tload Scheme source code from FILE, and exit\n"
"The above switches stop argument processing\n\n"
" -l FILE \tload Scheme source code from FILE\n"
" -h, --help \tdisplay this help and exit\n", cmd);
exit(0);
}
EmptyList *empty_list = new EmptyList();
UnspecObj *unspec_obj = new UnspecObj();
int main(int argc, char **argv) {
//freopen("in.scm", "r", stdin);
gc.attach(empty_list);
gc.attach(unspec_obj);
for (int i = 1; i < argc; i++)
{
if (*argv[i] == '-') // parsing options
{
if (strcmp(argv[i], "-l") == 0)
{
if (i + 1 < argc)
load_file(argv[++i]);
else
{
puts("missing argument to `-l` switch");
print_help(*argv);
}
}
else if (strcmp(argv[i], "-h") == 0 ||
strcmp(argv[i], "--help") == 0)
print_help(*argv);
else
{
printf("unrecognized switch `%s`\n", argv[i]);
print_help(*argv);
}
}
else
{
load_file(argv[i]);
exit(0);
}
}
int rcnt = 0;
tk.set_stream(stdin); // interactive mode
while (1)
{
fprintf(stderr, "Sonsi> ");
try
{
Pair *tree = ast.absorb(&tk);
if (!tree) break;
EvalObj *ret = eval.run_expr(tree);
string output = ret->ext_repr();
gc.expose(ret);
fprintf(stderr, "Ret> $%d = %s\n", rcnt++, output.c_str());
}
catch (GeneralError &e)
{
fprintf(stderr, "An error occured: %s\n", e.get_msg().c_str());
}
gc.collect();
}
}
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