int repl()
{
global_env = null_import_environment();
environment_t *env = global_env;
print_banner(env);
#if HAVE_LIBREADLINE
init_readline();
#endif
for(;;) {
static char *input = reinterpret_cast<char*>(1);
/*
* input == 1 is the ugliest hack ever to
* disoplay the imported_defaults message below,
* and also because of ANOTHER hack, the home-brewed
* exception system using longjumps. I think I need to
* rewrite... :)
*/
if ( input != reinterpret_cast<char*>(1) ) {
if ( (input = readline("#; mickey> ")) == NULL )
break; // end of input stream
if ( *trimr(input) == '\0' )
continue; // empty command
#ifdef HAVE_LIBREADLINE
add_history(input);
#endif
if ( exception_raised() ) {
backtrace();
backtrace_clear();
continue;
}
} else
input = strdup("");
TRY {
/*
* Must wrap import_defaults in try-catch
*/
{
static bool imported_defaults = false;
if ( !imported_defaults ) {
printf("\n");
printf(" To quit, hit CTRL+D or type (exit). Use (help) for an introduction.\n");
printf(" Distributed under the LGPL 2.1; see LICENSE\n");
printf("\n");
printf(" WARNING: There's no garbage collector in Mickey yet!\n");
printf("|#\n\n");
import_defaults(env);
imported_defaults = true;
// import (help) and (top-level) etc.
if ( !global_opts.empty_repl_env )
import(env, exports_repl, "(scheme repl)");
}
}
program_t *p = parse(input, env);
if ( p->parens < 0 )
raise(runtime_exception(format(
"parser: unbalanced parenthesis -> %ld", p->parens)));
// Read until we have balanced parenthesis
std::string s(input);
while ( p->parens != 0 ) {
if ( (input = readline("")) == NULL ) break;
if ( *trimr(input) == '\0' ) continue;
s += " ";
s += input;
delete p;
#ifdef HAVE_LIBREADLINE
free(input);
input = NULL;
#endif
p = parse(s.c_str(), env);
}
#ifdef HAVE_LIBREADLINE
if ( input ) free(input);
#endif
for ( cons_t *i = p->root; !nullp(i); i = cdr(i) ) {
cons_t *result = eval(car(i), p->globals);
if ( circularp(result) ) {
fflush(stdout);
fprintf(stderr, "Warning: List is circular\n");
cons_t *l = list(), *end = l;
for ( int n=0; n < MAX_CIRCULAR_DISPLAY_ITEMS; ++n ) {
end->car = car(result);
end->cdr = cons(nil());
end = cdr(end);
result = cdr(result);
}
end->car = symbol("...etc");
end->cdr = cons(nil());
printf("%s\n", sprint(l).c_str());
} else {
std::string s = sprint(result);
if ( !s.empty() )
printf("%s\n", s.c_str());
}
}
delete p;
}
CATCH (const exception_t& e) {
if ( *e.what() != '\0' )
fprintf(stderr, "%s\n", e.what());
backtrace();
backtrace_clear();
}
}
printf("\n");
return 0;
}
cons_t* proc_circularp(cons_t* p, environment_t*)
{
assert_length(p, 1);
assert_type(PAIR, car(p));
return boolean(circularp(car(p)));
}
