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#include <ctype.h>
#include <getopt.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "shorthand.h"
#include "string_view.c"
#include "readline.c"
#include "lexer.c"
#include "objects.c"
#include "parser.c"
#include "environment.c"
#include "primitives.c"
// FIXME: We are not worried right now about freeing memory, but we should in
// the future.
// TODO: Better error messages.
#define REPL_PROMPT "bdl> "
void
init(void) {
// Clear env.
for (size_t i = 0; i < ENV_SIZE; i++) {
environment[i] = (EnvSymbol){0};
}
// Initialize singletons.
obj_nil = make_empty_list();
obj_true = make_boolean(true);
obj_false = make_boolean(false);
// Add primitive functions.
environment[env_n++] = (EnvSymbol){MAKE_SYM("+"), make_procedure(proc_add)};
environment[env_n++] = (EnvSymbol){MAKE_SYM("-"), make_procedure(proc_sub)};
environment[env_n++] = (EnvSymbol){MAKE_SYM("*"), make_procedure(proc_mul)};
environment[env_n++] = (EnvSymbol){MAKE_SYM("/"), make_procedure(proc_div)};
environment[env_n++] = (EnvSymbol){MAKE_SYM("boolean?"), make_procedure(proc_is_boolean)};
environment[env_n++] = (EnvSymbol){MAKE_SYM("not"), make_procedure(proc_not)};
environment[env_n++] = (EnvSymbol){MAKE_SYM("and"), make_procedure(proc_and)};
environment[env_n++] = (EnvSymbol){MAKE_SYM("or"), make_procedure(proc_or)};
environment[env_n++] = (EnvSymbol){MAKE_SYM("if"), make_procedure(proc_if)};
environment[env_n++] = (EnvSymbol){MAKE_SYM("else"), obj_true};
environment[env_n++] = (EnvSymbol){MAKE_SYM("cond"), make_procedure(proc_cond)};
environment[env_n++] = (EnvSymbol){MAKE_SYM("display"), make_procedure(proc_display)};
environment[env_n++] = (EnvSymbol){MAKE_SYM("print"), make_procedure(proc_print)};
}
void
eval_line(FILE *fd, char delimiter) {
StringView line = read_line(fd, delimiter);
Tokens tokens = tokenize(line);
#if DEBUG
printf("N_TOKENS: %ld\n", tokens.n);
for (size_t i = 0; i < tokens.n; i++) {
printf("\tTYPE: %3d ", tokens.start[i].type);
printf("N: %3ld ", tokens.start[i].value.n);
printf("VALUE: ");
sv_write(tokens.start[i].value);
printf("\n");
}
#endif
while (tokens.n > 0) {
Object *ast = parse(&tokens);
if (ast) {
#if DEBUG
printf("AST: ");
display(ast);
printf("\n");
printf("EVAL: ");
#endif
if (display(eval(ast))) {
printf("\n");
};
}
}
}
void
run_repl(void) {
printf("BDL REPL (Press Ctrl-C to exit)\n");
while (true) {
printf(REPL_PROMPT);
eval_line(stdin, '\n');
}
}
void
run_file(char *file_name) {
#if DEBUG
printf("Executing file: %s\n", file_name);
#endif
FILE *fd = fopen(file_name, "r");
if (!fd) {
fprintf(stderr, "couldn't open file: %s\n", file_name);
exit(EXIT_FAILURE);
}
eval_line(fd, EOF);
fclose(fd);
}
void
print_usage(void) {
printf("Usage: %s [options] <filename>\n", BIN_NAME);
printf("\n");
printf("\t-i\tInteractive mode (REPL).\n");
printf("\t-x\tExecute expression from stdin.\n");
printf("\n");
}
int
main(int argc, char *argv[]) {
init();
int option;
while ((option = getopt(argc, argv, "ix")) != -1) {
switch (option) {
case 'i': {
// Interactive mode.
run_repl();
return EXIT_SUCCESS;
} break;
case 'x': {
// Execute expression from stdin.
eval_line(stdin, EOF);
return EXIT_SUCCESS;
} break;
default: {
print_usage();
return EXIT_FAILURE;
} break;
}
}
// Run from file.
if (optind != argc - 1) {
fprintf(stderr, "%s: No input file given.\n", BIN_NAME);
print_usage();
return EXIT_FAILURE;
}
char *file_name = argv[optind];
run_file(file_name);
return EXIT_SUCCESS;
}
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