@@ 7,7 7,7 @@ include Makefile.conf
 
 OBJS=src/builtins.o src/charbuf.o src/gc.o src/hashtable.o src/iter.o \
      src/parse.o src/ringbuf.o src/types.o src/util.o src/textcache.o \
-     src/module.o
+     src/module.o src/en.o
 
 # https://semver.org
 VERSION=1.1.0


@@ 83,7 83,7 @@ doc: FORCE
 
 test: all FORCE
 	rm -f cov*.html src/*.gcda
-	@python test.py scripts/tests
+	@cd scripts && python ../test.py tests -r ../bin/funlisp
 	gcovr -r src --html --html-details -o cov.html
 
 clean_doc:

@@ 1,6 1,7 @@
 builtins.o: src/builtins.c src/funlisp_internal.h inc/funlisp.h \
  src/iter.h src/ringbuf.h src/hashtable.h
 charbuf.o: src/charbuf.c src/charbuf.h
+en.o: src/en.c
 gc.o: src/gc.c src/funlisp_internal.h inc/funlisp.h src/iter.h \
  src/ringbuf.h src/hashtable.h
 hashtable.o: src/hashtable.c src/iter.h src/hashtable.h

@@ 875,6 875,7 @@ enum lisp_errno {
 	LE_EXIT,     /* exit the interpreter */
 	LE_ASSERT,   /* assertion error */
 	LE_VALUE,    /* invalid argument */
+	LE_ERRNO,    /* used for C library errors, does perror() */
 
 	LE_MAX_ERR   /* not a real error, don't use */
 };

@@ 1,9 1,12 @@
 (assert (equal? '(getattr a 'b) 'a.b))
 (assert (equal? '(getattr (getattr one 'two) 'three) 'one.two.three))
 
-(import example)
+(import os)
 
-(assert (equal? (getattr example 'foo) "bar"))
-(assert (equal? example.foo "bar"))
+(import filter)
+
+(assert (equal?
+          (filter.filter (lambda (v) (< v 3)) '(1 2 3 4 5))
+          '(1 2)))
 
 ; OUTPUT(0)

@@ 758,9 758,8 @@ static lisp_value *lisp_builtin_import(
 	if (!lisp_get_args(rt, arglist, "s", &sym))
 		return NULL;
 
-	mod = lisp_lookup_module(rt, sym);
-	if (!mod)
-		return lisp_error(rt, LE_NOTFOUND, "module not found");
+	mod = lisp_do_import(rt, sym);
+	lisp_error_check(mod);
 
 	lisp_scope_bind(scope, sym, (lisp_value*)mod);
 	return (lisp_value*)mod;

@@ 0,0 1,6 @@
+#include <errno.h>
+
+int get_errno(void)
+{
+	return errno;
+}

@@ 85,7 85,7 @@ struct lisp_runtime {
 	/* Maintain cache of lisp_string */
 	struct hashtable *strcache;
 	/* Maintain builtin module list */
-	struct hashtable *modules;
+	lisp_scope *modules;
 };
 
 /* The below ARE lisp_values! */


@@ 196,8 196,12 @@ void lisp_textcache_remove(struct hashtable *cache, struct lisp_text *t);
 
 int lisp_truthy(lisp_value *v);
 
-/* Module stuff */
+/* Module stuff, will become public eventually, but for now is private */
 lisp_module *create_os_module(lisp_runtime *rt);
 void lisp_register_module(lisp_runtime *rt, lisp_module *m);
 lisp_module *lisp_lookup_module(lisp_runtime *rt, lisp_symbol *name);
+
+lisp_module *lisp_import_file(lisp_runtime *rt, lisp_string *name, lisp_string *file);
+lisp_module *lisp_do_import(lisp_runtime *rt, lisp_symbol *name);
+int get_errno(void);
 #endif

@@ 24,8 24,7 @@ void lisp_init(lisp_runtime *rt)
 	rt->stack_depth = 0;
 	rt->symcache = NULL;
 	rt->strcache = NULL;
-	rt->modules = ht_create(lisp_text_hash, lisp_text_compare,
-		sizeof(struct lisp_text *), sizeof(struct lisp_module*));
+	rt->modules = lisp_new_empty_scope(rt);
 
 	lisp_register_module(rt, create_os_module(rt));
 }


@@ 40,7 39,6 @@ void lisp_destroy(lisp_runtime *rt)
 		ht_delete(rt->symcache);
 	if (rt->strcache)
 		ht_delete(rt->strcache);
-	ht_delete(rt->modules);
 }
 
 void lisp_mark(lisp_runtime *rt, lisp_value *v)


@@ 75,6 73,7 @@ static void lisp_mark_basics(lisp_runtime *rt)
 	if (rt->error_stack)
 		lisp_mark(rt, (lisp_value *) rt->error_stack);
 	lisp_mark(rt, (lisp_value *) rt->stack);
+	lisp_mark(rt, (lisp_value *) rt->modules);
 }
 
 void lisp_sweep(lisp_runtime *rt)

@@ 2,6 2,7 @@
  * Module-related functionality. Includes builtin modules.
  */
 #include <stdlib.h>
+#include <string.h>
 
 #include "funlisp_internal.h"
 


@@ 43,10 44,62 @@ lisp_module *create_os_module(lisp_runtime *rt)
 
 void lisp_register_module(lisp_runtime *rt, lisp_module *m)
 {
-	ht_insert_ptr(rt->modules, m->name, m);
+	/* TODO this depends on symbols and strings hashing to same value and
+	 * comparing equal */
+	lisp_scope_bind(rt->modules, (lisp_symbol*)m->name, (lisp_value*) m);
 }
 
 lisp_module *lisp_lookup_module(lisp_runtime *rt, lisp_symbol *name)
 {
-	return ht_get_ptr(rt->modules, name);
+	lisp_module *m = (lisp_module*) lisp_scope_lookup(rt, rt->modules, name);
+
+	if (!m) /* not found is not necessarily an error */
+		lisp_clear_error(rt);
+
+	return m;
+}
+
+lisp_module *lisp_import_file(lisp_runtime *rt, lisp_string *name, lisp_string *file)
+{
+	FILE *f;
+	lisp_scope *builtins = lisp_new_default_scope(rt);
+	lisp_scope *modscope = lisp_new_empty_scope(rt);
+	lisp_module *module;
+	lisp_value *v;
+	modscope->up = builtins;
+
+	f = fopen(file->s, "r");
+	if (!f) {
+		return (lisp_module*) lisp_error(rt, LE_ERRNO, "error opening file for import");
+	}
+
+	v = lisp_load_file(rt, modscope, f);
+	lisp_error_check(v);
+
+	module = (lisp_module *)lisp_new(rt, type_module);
+	module->contents = modscope;
+	module->name = name;
+	module->file = file;
+	lisp_register_module(rt, module);
+	return module;
+}
+
+lisp_module *lisp_do_import(lisp_runtime *rt, lisp_symbol *name)
+{
+	lisp_module *m;
+	lisp_string *file, *namestr;
+	char *filestr;
+	int len;
+
+	m = lisp_lookup_module(rt, name);
+	if (m)
+		return m;
+
+	len = strlen(name->s);
+	len += 1 /*nul*/ + 7 /*./ .lisp */;
+	filestr = malloc(len);
+	sprintf(filestr, "./%s.lisp", name->s);
+	file = lisp_string_new(rt, filestr, LS_OWN);
+	namestr = lisp_symbol_new(rt, name->s, LS_OWN | LS_CPY);
+	return lisp_import_file(rt, namestr, file);
 }

@@ 179,7 179,7 @@ static struct iterator scope_expand(lisp_value *v)
 	lisp_scope *scope = (lisp_scope *) v;
 	if (scope->up) {
 		return iterator_concat3(
-			iterator_single_value(&scope->up),
+			iterator_single_value(scope->up),
 			ht_iter_keys_ptr(&scope->scope),
 			ht_iter_values_ptr(&scope->scope)
 		);

@@ 33,6 33,7 @@ const char *lisp_error_name[LE_MAX_ERR] = {
 	"LE_EXIT",
 	"LE_ASSERT",
 	"LE_VALUE",
+	"LE_ERRNO",
 };
 
 void lisp_scope_bind(lisp_scope *scope, lisp_symbol *symbol, lisp_value *value)


@@ 413,6 414,7 @@ void lisp_clear_error(lisp_runtime *rt)
 
 void lisp_print_error(lisp_runtime *rt, FILE *file)
 {
+	char *errmsg;
 	if (!rt->error) {
 		fprintf(stderr, "BUG: lisp_print_error() expects error, found none\n");
 		return;


@@ 421,7 423,13 @@ void lisp_print_error(lisp_runtime *rt, FILE *file)
 	if (rt->error_line)
 		fprintf(file, "at line %d: ", rt->error_line);
 
-	fprintf(file, "Error %s: %s\n", lisp_error_name[rt->errno], rt->error);
+	if (rt->errno == LE_ERRNO) {
+		errmsg = strerror(get_errno());
+		fprintf(file, "Error %s: %s\nSystem error: %s\n",
+			lisp_error_name[rt->errno], rt->error, errmsg);
+	} else {
+		fprintf(file, "Error %s: %s\n", lisp_error_name[rt->errno], rt->error);
+	}
 
 	if (rt->error_stack)
 		lisp_dump_stack(rt, rt->error_stack, file);