diff --git a/README.md b/README.md
index d3d01b39f..ddc2b0bef 100644
--- a/README.md
+++ b/README.md
@@ -762,6 +762,8 @@ A server *Goal* takes a single arg, the connection stream.
 Networking					##EXPERIMENTAL##
 ==========
 
+	parse_url/2             # parse_url(?atom,?list)
+
 	server/2                # server(+host,-stream)
 	server/3                # server(+host,-stream,+list)
 	accept/2                # accept(+stream,-stream)
diff --git a/src/control.c b/src/control.c
index 330a60265..fa7ee2ca4 100644
--- a/src/control.c
+++ b/src/control.c
@@ -759,8 +759,8 @@ bool throw_error3(query *q, cell *c, pl_idx c_ctx, const char *err_type, const c
 		check_heap_error(tmp);
 		pl_idx nbr_cells = 0;
 		make_struct(tmp+nbr_cells++, g_error_s, NULL, 2, 2);
-		make_atom(tmp+nbr_cells++, index_from_pool(q->pl, err_type));
-		make_atom(tmp+nbr_cells, index_from_pool(q->pl, expected));
+		make_atom(tmp+nbr_cells++, new_atom(q->pl, err_type));
+		make_atom(tmp+nbr_cells, new_atom(q->pl, expected));
 	} else if (!strcmp(err_type, "type_error") && !strcmp(expected, "var")) {
 		err_type = "uninstantiation_error";
 		//printf("error(%s(%s),(%s)/%u).\n", err_type, C_STR(q, c), functor, goal->arity);
@@ -768,12 +768,12 @@ bool throw_error3(query *q, cell *c, pl_idx c_ctx, const char *err_type, const c
 		check_heap_error(tmp);
 		pl_idx nbr_cells = 0;
 		make_struct(tmp+nbr_cells++, g_error_s, NULL, 2, 5+(c->nbr_cells-1));
-		make_struct(tmp+nbr_cells++, index_from_pool(q->pl, err_type), NULL, 1, 1+(c->nbr_cells-1));
+		make_struct(tmp+nbr_cells++, new_atom(q->pl, err_type), NULL, 1, 1+(c->nbr_cells-1));
 		safe_copy_cells(tmp+nbr_cells, c, c->nbr_cells);
 		nbr_cells += c->nbr_cells;
 		make_struct(tmp+nbr_cells, g_slash_s, NULL, 2, 2);
 		SET_OP(tmp+nbr_cells, OP_YFX); nbr_cells++;
-		make_atom(tmp+nbr_cells++, index_from_pool(q->pl, functor));
+		make_atom(tmp+nbr_cells++, new_atom(q->pl, functor));
 		make_int(tmp+nbr_cells, !is_string(goal)?goal->arity:0);
 	} else if (!strcmp(err_type, "type_error") && !strcmp(expected, "evaluable")) {
 		//printf("error(%s(%s,(%s)/%u),(%s)/%u).\n", err_type, expected, C_STR(q, c), c->arity, functor, goal->arity);
@@ -781,8 +781,8 @@ bool throw_error3(query *q, cell *c, pl_idx c_ctx, const char *err_type, const c
 		check_heap_error(tmp);
 		pl_idx nbr_cells = 0;
 		make_struct(tmp+nbr_cells++, g_error_s, NULL, 2, 8);
-		make_struct(tmp+nbr_cells++, index_from_pool(q->pl, err_type), NULL, 2, 4);
-		make_atom(tmp+nbr_cells++, index_from_pool(q->pl, expected));
+		make_struct(tmp+nbr_cells++, new_atom(q->pl, err_type), NULL, 2, 4);
+		make_atom(tmp+nbr_cells++, new_atom(q->pl, expected));
 		make_struct(tmp+nbr_cells, g_slash_s, NULL, 2, 2);
 		SET_OP(tmp+nbr_cells, OP_YFX); nbr_cells++;
 		tmp[nbr_cells] = *c;
@@ -792,7 +792,7 @@ bool throw_error3(query *q, cell *c, pl_idx c_ctx, const char *err_type, const c
 		make_int(tmp+nbr_cells++, c->arity);
 		make_struct(tmp+nbr_cells, g_slash_s, NULL, 2, 2);
 		SET_OP(tmp+nbr_cells, OP_YFX); nbr_cells++;
-		make_atom(tmp+nbr_cells++, index_from_pool(q->pl, functor));
+		make_atom(tmp+nbr_cells++, new_atom(q->pl, functor));
 		make_int(tmp+nbr_cells, !is_string(goal)?goal->arity:0);
 	} else if (!strcmp(err_type, "permission_error") && is_structure(c) && CMP_STR_TO_CSTR(q, c, "/") && is_var(FIRST_ARG(c))) {
 		//printf("error(%s(%s,(%s)/%u),(%s)/%u).\n", err_type, expected, tmpbuf, c->arity, functor, goal->arity);
@@ -800,10 +800,10 @@ bool throw_error3(query *q, cell *c, pl_idx c_ctx, const char *err_type, const c
 		check_heap_error(tmp);
 		pl_idx nbr_cells = 0;
 		make_struct(tmp+nbr_cells++, g_error_s, NULL, 2, 8+extra);
-		make_struct(tmp+nbr_cells++, index_from_pool(q->pl, err_type), NULL, 2+extra, 4+extra);
+		make_struct(tmp+nbr_cells++, new_atom(q->pl, err_type), NULL, 2+extra, 4+extra);
 
 		if (!extra)
-			make_atom(tmp+nbr_cells++, index_from_pool(q->pl, expected));
+			make_atom(tmp+nbr_cells++, new_atom(q->pl, expected));
 		else {
 			char tmpbuf[1024*8];
 			strcpy(tmpbuf, expected);
@@ -812,12 +812,12 @@ bool throw_error3(query *q, cell *c, pl_idx c_ctx, const char *err_type, const c
 			if (*ptr2) *ptr2++ = '\0';
 
 			while (ptr2) {
-				make_atom(tmp+nbr_cells++, index_from_pool(q->pl, ptr));
+				make_atom(tmp+nbr_cells++, new_atom(q->pl, ptr));
 				ptr = ptr2;
 				ptr2 = strchr(ptr, ',');
 			}
 
-			make_atom(tmp+nbr_cells++, index_from_pool(q->pl, ptr));
+			make_atom(tmp+nbr_cells++, new_atom(q->pl, ptr));
 		}
 
 		make_struct(tmp+nbr_cells, g_slash_s, NULL, 2, 2);
@@ -829,7 +829,7 @@ bool throw_error3(query *q, cell *c, pl_idx c_ctx, const char *err_type, const c
 		make_int(tmp+nbr_cells++, c->arity);
 		make_struct(tmp+nbr_cells, g_slash_s, NULL, 2, 2);
 		SET_OP(tmp+nbr_cells, OP_YFX); nbr_cells++;
-		make_atom(tmp+nbr_cells++, index_from_pool(q->pl, functor));
+		make_atom(tmp+nbr_cells++, new_atom(q->pl, functor));
 		make_int(tmp+nbr_cells, !is_string(goal)?goal->arity:0);
 	} else if (!strcmp(err_type, "permission_error") && (is_builtin || (is_op && c->arity)) && !is_abolish) {
 		//printf("error(%s(%s,(%s)/%u),(%s)/%u).\n", err_type, expected, tmpbuf, c->arity, functor, goal->arity);
@@ -837,10 +837,10 @@ bool throw_error3(query *q, cell *c, pl_idx c_ctx, const char *err_type, const c
 		check_heap_error(tmp);
 		pl_idx nbr_cells = 0;
 		make_struct(tmp+nbr_cells++, g_error_s, NULL, 2, 8+extra);
-		make_struct(tmp+nbr_cells++, index_from_pool(q->pl, err_type), NULL, 2+extra, 4+extra);
+		make_struct(tmp+nbr_cells++, new_atom(q->pl, err_type), NULL, 2+extra, 4+extra);
 
 		if (!extra)
-			make_atom(tmp+nbr_cells++, index_from_pool(q->pl, expected));
+			make_atom(tmp+nbr_cells++, new_atom(q->pl, expected));
 		else {
 			char tmpbuf[1024*8];
 			strcpy(tmpbuf, expected);
@@ -849,12 +849,12 @@ bool throw_error3(query *q, cell *c, pl_idx c_ctx, const char *err_type, const c
 			if (*ptr2) *ptr2++ = '\0';
 
 			while (ptr2) {
-				make_atom(tmp+nbr_cells++, index_from_pool(q->pl, ptr));
+				make_atom(tmp+nbr_cells++, new_atom(q->pl, ptr));
 				ptr = ptr2;
 				ptr2 = strchr(ptr, ',');
 			}
 
-			make_atom(tmp+nbr_cells++, index_from_pool(q->pl, ptr));
+			make_atom(tmp+nbr_cells++, new_atom(q->pl, ptr));
 		}
 
 		make_struct(tmp+nbr_cells, g_slash_s, NULL, 2, 2);
@@ -866,7 +866,7 @@ bool throw_error3(query *q, cell *c, pl_idx c_ctx, const char *err_type, const c
 		make_int(tmp+nbr_cells++, c->arity);
 		make_struct(tmp+nbr_cells, g_slash_s, NULL, 2, 2);
 		SET_OP(tmp+nbr_cells, OP_YFX); nbr_cells++;
-		make_atom(tmp+nbr_cells++, index_from_pool(q->pl, functor));
+		make_atom(tmp+nbr_cells++, new_atom(q->pl, functor));
 		make_int(tmp+nbr_cells, !is_string(goal)?goal->arity:0);
 	} else if (!strcmp(err_type, "instantiation_error")) {
 		//printf("error(%s,(%s)/%u).\n", err_type, functor, goal->arity);
@@ -874,10 +874,10 @@ bool throw_error3(query *q, cell *c, pl_idx c_ctx, const char *err_type, const c
 		check_heap_error(tmp);
 		pl_idx nbr_cells = 0;
 		make_struct(tmp+nbr_cells++, g_error_s, NULL, 2, 4);
-		make_atom(tmp+nbr_cells++, index_from_pool(q->pl, err_type));
+		make_atom(tmp+nbr_cells++, new_atom(q->pl, err_type));
 		make_struct(tmp+nbr_cells, g_slash_s, NULL, 2, 2);
 		SET_OP(tmp+nbr_cells, OP_YFX); nbr_cells++;
-		make_atom(tmp+nbr_cells++, index_from_pool(q->pl, functor));
+		make_atom(tmp+nbr_cells++, new_atom(q->pl, functor));
 		make_int(tmp+nbr_cells, !is_string(goal)?goal->arity:0);
 	} else if (!strcmp(err_type, "existence_error") && !strcmp(expected, "procedure") && is_callable(c)) {
 		//printf("error(%s(%s,(%s)/%u),(%s)/%u).\n", err_type, expected, tmpbuf, c->arity, functor, goal->arity);
@@ -885,15 +885,15 @@ bool throw_error3(query *q, cell *c, pl_idx c_ctx, const char *err_type, const c
 		check_heap_error(tmp);
 		pl_idx nbr_cells = 0;
 		make_struct(tmp+nbr_cells++, g_error_s, NULL, 2, 8);
-		make_struct(tmp+nbr_cells++, index_from_pool(q->pl, err_type), NULL, 2, 4);
-		make_atom(tmp+nbr_cells++, index_from_pool(q->pl, expected));
+		make_struct(tmp+nbr_cells++, new_atom(q->pl, err_type), NULL, 2, 4);
+		make_atom(tmp+nbr_cells++, new_atom(q->pl, expected));
 		make_struct(tmp+nbr_cells, g_slash_s, NULL, 2, 2);
 		SET_OP(tmp+nbr_cells, OP_YFX); nbr_cells++;
-		make_atom(tmp+nbr_cells++, index_from_pool(q->pl, C_STR(q, c)));
+		make_atom(tmp+nbr_cells++, new_atom(q->pl, C_STR(q, c)));
 		make_int(tmp+nbr_cells++, c->arity);
 		make_struct(tmp+nbr_cells, g_slash_s, NULL, 2, 2);
 		SET_OP(tmp+nbr_cells, OP_YFX); nbr_cells++;
-		make_atom(tmp+nbr_cells++, index_from_pool(q->pl, functor));
+		make_atom(tmp+nbr_cells++, new_atom(q->pl, functor));
 		make_int(tmp+nbr_cells, !is_string(goal)?goal->arity:0);
 	} else if (!strcmp(err_type, "representation_error")
 		|| !strcmp(err_type, "evaluation_error")
@@ -904,11 +904,11 @@ bool throw_error3(query *q, cell *c, pl_idx c_ctx, const char *err_type, const c
 		check_heap_error(tmp);
 		pl_idx nbr_cells = 0;
 		make_struct(tmp+nbr_cells++, g_error_s, NULL, 2, 5);
-		make_struct(tmp+nbr_cells++, index_from_pool(q->pl, err_type), NULL, 1, 1);
-		make_atom(tmp+nbr_cells++, index_from_pool(q->pl, expected));
+		make_struct(tmp+nbr_cells++, new_atom(q->pl, err_type), NULL, 1, 1);
+		make_atom(tmp+nbr_cells++, new_atom(q->pl, expected));
 		make_struct(tmp+nbr_cells, g_slash_s, NULL, 2, 2);
 		SET_OP(tmp+nbr_cells, OP_YFX); nbr_cells++;
-		make_atom(tmp+nbr_cells++, index_from_pool(q->pl, functor));
+		make_atom(tmp+nbr_cells++, new_atom(q->pl, functor));
 		make_int(tmp+nbr_cells, !is_string(goal)?goal->arity:0);
 	} else {
 		//printf("error(%s(%s,(%s)),(%s)/%u).\n", err_type, expected, C_STR(q, c), functor, goal->arity);
@@ -916,10 +916,10 @@ bool throw_error3(query *q, cell *c, pl_idx c_ctx, const char *err_type, const c
 		check_heap_error(tmp);
 		pl_idx nbr_cells = 0;
 		make_struct(tmp+nbr_cells++, g_error_s, NULL, 2, 6+(c->nbr_cells-1)+extra);
-		make_struct(tmp+nbr_cells++, index_from_pool(q->pl, err_type), NULL, 2+extra, 2+(c->nbr_cells-1)+extra);
+		make_struct(tmp+nbr_cells++, new_atom(q->pl, err_type), NULL, 2+extra, 2+(c->nbr_cells-1)+extra);
 
 		if (!extra) {
-			make_atom(tmp+nbr_cells++, index_from_pool(q->pl, expected));
+			make_atom(tmp+nbr_cells++, new_atom(q->pl, expected));
 		} else {
 			char tmpbuf[1024*8];
 			strcpy(tmpbuf, expected);
@@ -928,18 +928,18 @@ bool throw_error3(query *q, cell *c, pl_idx c_ctx, const char *err_type, const c
 			if (*ptr2) *ptr2++ = '\0';
 
 			while (ptr2) {
-				make_atom(tmp+nbr_cells++, index_from_pool(q->pl, ptr));
+				make_atom(tmp+nbr_cells++, new_atom(q->pl, ptr));
 				ptr = ptr2;
 				ptr2 = strchr(ptr, ',');
 			}
 
-			make_atom(tmp+nbr_cells++, index_from_pool(q->pl, ptr));
+			make_atom(tmp+nbr_cells++, new_atom(q->pl, ptr));
 		}
 
 		nbr_cells += safe_copy_cells(tmp+nbr_cells, c, c->nbr_cells);
 		make_struct(tmp+nbr_cells, g_slash_s, NULL, 2, 2);
 		SET_OP(tmp+nbr_cells, OP_YFX); nbr_cells++;
-		make_atom(tmp+nbr_cells++, index_from_pool(q->pl, functor));
+		make_atom(tmp+nbr_cells++, new_atom(q->pl, functor));
 		make_int(tmp+nbr_cells, !is_string(goal)?goal->arity:0);
 	}
 
diff --git a/src/heap.c b/src/heap.c
index 0b1dbf65a..9b16fedb0 100644
--- a/src/heap.c
+++ b/src/heap.c
@@ -667,7 +667,7 @@ void allocate_structure(query *q, const char *functor, const cell *c)
 	if (!tmp) return;
 	tmp->tag = TAG_INTERNED;
 	tmp->nbr_cells = 1;
-	tmp->val_off = index_from_pool(q->pl, functor);
+	tmp->val_off = new_atom(q->pl, functor);
 	tmp->arity = 0;
 	tmp->flags = 0;
 	append_structure(q, c);
diff --git a/src/module.c b/src/module.c
index 07cd1c406..aed9e6312 100644
--- a/src/module.c
+++ b/src/module.c
@@ -296,7 +296,7 @@ static predicate *find_predicate_(module *m, cell *c, bool abolished)
 	tmp.nbr_cells = 1;
 
 	if (is_cstring(c)) {
-		tmp.val_off = index_from_pool(m->pl, C_STR(m, c));
+		tmp.val_off = new_atom(m->pl, C_STR(m, c));
 	}
 
 	sliter *iter = sl_find_key(m->index, &tmp);
@@ -596,7 +596,7 @@ void set_discontiguous_in_db(module *m, const char *name, unsigned arity)
 {
 	cell tmp = (cell){0};
 	tmp.tag = TAG_INTERNED;
-	tmp.val_off = index_from_pool(m->pl, name);
+	tmp.val_off = new_atom(m->pl, name);
 	ensure(tmp.val_off != ERR_IDX);
 	tmp.arity = arity;
 	predicate *pr = find_predicate(m, &tmp);
@@ -613,7 +613,7 @@ void set_multifile_in_db(module *m, const char *name, pl_idx arity)
 {
 	cell tmp = (cell){0};
 	tmp.tag = TAG_INTERNED;
-	tmp.val_off = index_from_pool(m->pl, name);
+	tmp.val_off = new_atom(m->pl, name);
 	ensure(tmp.val_off != ERR_IDX);
 	tmp.arity = arity;
 	predicate *pr = find_predicate(m, &tmp);
@@ -630,7 +630,7 @@ void set_dynamic_in_db(module *m, const char *name, unsigned arity)
 {
 	cell tmp = (cell){0};
 	tmp.tag = TAG_INTERNED;
-	tmp.val_off = index_from_pool(m->pl, name);
+	tmp.val_off = new_atom(m->pl, name);
 	ensure(tmp.val_off != ERR_IDX);
 	tmp.arity = arity;
 	predicate *pr = find_predicate(m, &tmp);
@@ -649,7 +649,7 @@ void set_meta_predicate_in_db(module *m, cell *c)
 	unsigned arity = c->arity;
 	cell tmp = (cell){0};
 	tmp.tag = TAG_INTERNED;
-	tmp.val_off = index_from_pool(m->pl, name);
+	tmp.val_off = new_atom(m->pl, name);
 	ensure(tmp.val_off != ERR_IDX);
 	tmp.arity = arity;
 	predicate *pr = find_predicate(m, &tmp);
@@ -953,7 +953,7 @@ bool do_use_foreign_module(module *m, cell *p)
 void convert_to_literal(module *m, cell *c)
 {
 	char *src = DUP_STR(m, c);
-	pl_idx off = index_from_pool(m->pl, src);
+	pl_idx off = new_atom(m->pl, src);
 	unshare_cell(c);
 	c->tag = TAG_INTERNED;
 	c->val_off = off;
@@ -971,7 +971,7 @@ predicate *find_functor(module *m, const char *name, unsigned arity)
 {
 	cell tmp = (cell){0};
 	tmp.tag = TAG_INTERNED;
-	tmp.val_off = index_from_pool(m->pl, name);
+	tmp.val_off = new_atom(m->pl, name);
 	tmp.arity = arity;
 	return find_predicate(m, &tmp);
 }
diff --git a/src/parser.c b/src/parser.c
index ce1326635..fa60f440d 100644
--- a/src/parser.c
+++ b/src/parser.c
@@ -580,7 +580,7 @@ static bool directives(parser *p, cell *d)
 	if (d->arity != 1)
 		return false;
 
-	d->val_off = index_from_pool(p->pl, "$directive");
+	d->val_off = new_atom(p->pl, "$directive");
 	CLR_OP(d);
 
 	if (!strcmp(dirname, "initialization") && (c->arity == 1)) {
@@ -1611,7 +1611,7 @@ static bool dcg_expansion(parser *p)
 
 	cell *c = p->cl->cells;
 	cell *tmp = alloc_on_heap(q, 1+c->nbr_cells+1+1);
-	make_struct(tmp, index_from_pool(p->pl, "dcg_translate"), NULL, 2, c->nbr_cells+1);
+	make_struct(tmp, new_atom(p->pl, "dcg_translate"), NULL, 2, c->nbr_cells+1);
 	safe_copy_cells(tmp+1, p->cl->cells, c->nbr_cells);
 	make_ref(tmp+1+c->nbr_cells, g_anon_s, p->cl->nbr_vars, 0);
 	make_end(tmp+1+c->nbr_cells+1);
@@ -3051,7 +3051,7 @@ static bool process_term(parser *p, cell *p1)
 	}
 
 	if (is_cstring(h)) {
-		pl_idx off = index_from_pool(p->m->pl, C_STR(p, h));
+		pl_idx off = new_atom(p->m->pl, C_STR(p, h));
 		if (off == ERR_IDX) {
 			p->error = true;
 			return false;
@@ -3709,7 +3709,7 @@ unsigned tokenize(parser *p, bool args, bool consing)
 			if (p->is_quoted)
 				c->flags |= FLAG_CSTR_QUOTED;
 
-			c->val_off = index_from_pool(p->m->pl, SB_cstr(p->token));
+			c->val_off = new_atom(p->m->pl, SB_cstr(p->token));
 			ensure(c->val_off != ERR_IDX);
 		} else {
 			c->tag = TAG_CSTR;
diff --git a/src/predicates.c b/src/predicates.c
index f85e6cd45..d3fee8906 100644
--- a/src/predicates.c
+++ b/src/predicates.c
@@ -2359,7 +2359,7 @@ static void do_term_assign_vars(parser *p)
 		else
 			snprintf(tmpbuf, sizeof(tmpbuf), "%c%d", ch, n);
 
-		c->val_off = index_from_pool(p->m->pl, tmpbuf);
+		c->val_off = new_atom(p->m->pl, tmpbuf);
 		c->flags = 0;
 	}
 }
@@ -2516,7 +2516,7 @@ static bool fn_iso_functor_3(query *q)
 			tmp[0].nbr_cells = 1 + arity;
 
 			if (is_cstring(p2)) {
-				tmp[0].val_off = index_from_pool(q->pl, C_STR(q, p2));
+				tmp[0].val_off = new_atom(q->pl, C_STR(q, p2));
 			} else
 				tmp[0].val_off = p2->val_off;
 
@@ -2594,7 +2594,7 @@ static bool fn_iso_current_rule_1(query *q)
 
 	cell tmp = (cell){0};
 	tmp.tag = TAG_INTERNED;
-	tmp.val_off = index_from_pool(q->pl, functor);
+	tmp.val_off = new_atom(q->pl, functor);
 	tmp.arity = arity;
 
 	if (search_predicate(q->st.m, &tmp, NULL))
@@ -2698,7 +2698,7 @@ static bool fn_iso_current_predicate_1(query *q)
 
 	cell tmp = (cell){0};
 	tmp.tag = TAG_INTERNED;
-	tmp.val_off = is_interned(p1) ? p1->val_off : index_from_pool(q->pl, C_STR(q, p1));
+	tmp.val_off = is_interned(p1) ? p1->val_off : new_atom(q->pl, C_STR(q, p1));
 	tmp.arity = get_smallint(p2);
 	bool is_prebuilt = false;
 	bool ok = search_predicate(q->st.m, &tmp, &is_prebuilt) != NULL;
@@ -2726,11 +2726,11 @@ static bool fn_iso_current_prolog_flag_2(query *q)
 		cell tmp;
 
 		if (q->st.m->flags.double_quote_atom)
-			make_atom(&tmp, index_from_pool(q->pl, "atom"));
+			make_atom(&tmp, new_atom(q->pl, "atom"));
 		else if (q->st.m->flags.double_quote_codes)
-			make_atom(&tmp, index_from_pool(q->pl, "codes"));
+			make_atom(&tmp, new_atom(q->pl, "codes"));
 		else if (q->st.m->flags.double_quote_chars)
-			make_atom(&tmp, index_from_pool(q->pl, "chars"));
+			make_atom(&tmp, new_atom(q->pl, "chars"));
 
 		return unify(q, p2, p2_ctx, &tmp, q->st.curr_frame);
 	} else if (!CMP_STR_TO_CSTR(q, p1, "char_conversion")) {
@@ -2758,12 +2758,12 @@ static bool fn_iso_current_prolog_flag_2(query *q)
 		else if (q->st.m->flags.occurs_check == OCCURS_CHECK_FALSE)
 			make_atom(&tmp, g_false_s);
 		else
-			make_atom(&tmp, index_from_pool(q->pl, "error"));
+			make_atom(&tmp, new_atom(q->pl, "error"));
 
 		return unify(q, p2, p2_ctx, &tmp, q->st.curr_frame);
 	} else if (!CMP_STR_TO_CSTR(q, p1, "encoding")) {
 		cell tmp;
-		make_atom(&tmp, index_from_pool(q->pl, "UTF-8"));
+		make_atom(&tmp, new_atom(q->pl, "UTF-8"));
 		return unify(q, p2, p2_ctx, &tmp, q->st.curr_frame);
 	} else if (!CMP_STR_TO_CSTR(q, p1, "strict_iso")) {
 		cell tmp;
@@ -2794,11 +2794,11 @@ static bool fn_iso_current_prolog_flag_2(query *q)
 		return unify(q, p2, p2_ctx, &tmp, q->st.curr_frame);
 	} else if (!CMP_STR_TO_CSTR(q, p1, "dialect")) {
 		cell tmp;
-		make_atom(&tmp, index_from_pool(q->pl, "trealla"));
+		make_atom(&tmp, new_atom(q->pl, "trealla"));
 		return unify(q, p2, p2_ctx, &tmp, q->st.curr_frame);
 	} else if (!CMP_STR_TO_CSTR(q, p1, "integer_rounding_function")) {
 		cell tmp;
-		make_atom(&tmp, index_from_pool(q->pl, "toward_zero"));
+		make_atom(&tmp, new_atom(q->pl, "toward_zero"));
 		return unify(q, p2, p2_ctx, &tmp, q->st.curr_frame);
 	} else if (!CMP_STR_TO_CSTR(q, p1, "bounded")) {
 		cell tmp;
@@ -2827,7 +2827,7 @@ static bool fn_iso_current_prolog_flag_2(query *q)
 		sscanf(g_version, "v%u.%u.%u", &v1, &v2, &v3);
 		cell *tmp = alloc_on_heap(q, 5);
 		check_heap_error(tmp);
-		make_atom(&tmp[0], index_from_pool(q->pl, "trealla"));
+		make_atom(&tmp[0], new_atom(q->pl, "trealla"));
 		make_int(&tmp[1], v1);
 		make_int(&tmp[2], v2);
 		make_int(&tmp[3], v3);
@@ -2837,7 +2837,7 @@ static bool fn_iso_current_prolog_flag_2(query *q)
 		return unify(q, p2, p2_ctx, tmp, q->st.curr_frame);
 	} else if (!CMP_STR_TO_CSTR(q, p1, "version_git")) {
 		cell tmp;
-		make_atom(&tmp, index_from_pool(q->pl, g_version));
+		make_atom(&tmp, new_atom(q->pl, g_version));
 		return unify(q, p2, p2_ctx, &tmp, q->st.curr_frame);
 	} else if (!CMP_STR_TO_CSTR(q, p1, "argv")) {
 		if (g_avc >= g_ac)
@@ -2859,10 +2859,10 @@ static bool fn_iso_current_prolog_flag_2(query *q)
 	} else if (!CMP_STR_TO_CSTR(q, p1, "unknown")) {
 		cell tmp;
 		make_atom(&tmp,
-			q->st.m->flags.unknown == UNK_ERROR ? index_from_pool(q->pl, "error") :
-			q->st.m->flags.unknown == UNK_WARNING ? index_from_pool(q->pl, "warning") :
-			q->st.m->flags.unknown == UNK_CHANGEABLE ? index_from_pool(q->pl, "changeable") :
-			index_from_pool(q->pl, "fail"));
+			q->st.m->flags.unknown == UNK_ERROR ? new_atom(q->pl, "error") :
+			q->st.m->flags.unknown == UNK_WARNING ? new_atom(q->pl, "warning") :
+			q->st.m->flags.unknown == UNK_CHANGEABLE ? new_atom(q->pl, "changeable") :
+			new_atom(q->pl, "fail"));
 		return unify(q, p2, p2_ctx, &tmp, q->st.curr_frame);
 	} else if (!CMP_STR_TO_CSTR(q, p1, "generate_debug_info")) {
 	}
@@ -3921,7 +3921,7 @@ static bool fn_listing_1(query *q)
 		if (!is_integer(p3))
 			return throw_error(q, p3, p1_ctx, "type_error", "integer");
 
-		name = index_from_pool(q->pl, C_STR(q, p2));
+		name = new_atom(q->pl, C_STR(q, p2));
 		arity = get_smallint(p3);
 
 		if (!CMP_STR_TO_CSTR(q, p1, "//"))
@@ -4023,10 +4023,10 @@ static bool fn_source_info_2(query *q)
 	for (db_entry *dbe = pr->head; dbe; dbe = dbe->next) {
 		cell tmp[8];
 		make_struct(tmp+0, g_dot_s, NULL, 2, 7);
-		make_struct(tmp+1, index_from_pool(q->pl, "filename"), NULL, 1, 1);
+		make_struct(tmp+1, new_atom(q->pl, "filename"), NULL, 1, 1);
 		make_cstring(tmp+2, dbe->filename);
 		make_struct(tmp+3, g_dot_s, NULL, 2, 4);
-		make_struct(tmp+4, index_from_pool(q->pl, "lines"), NULL, 2, 2);
+		make_struct(tmp+4, new_atom(q->pl, "lines"), NULL, 2, 2);
 		make_uint(tmp+5, dbe->line_nbr_start);
 		make_uint(tmp+6, dbe->line_nbr_end);
 		make_atom(tmp+7, g_nil_s);
@@ -5672,7 +5672,7 @@ static bool fn_crypto_data_hash_3(query *q)
 			if (!CMP_STR_TO_CSTR(q, h, "algorithm")) {
 				if (is_var(arg)) {
 					cell tmp;
-					make_atom(&tmp, index_from_pool(q->pl, "sha256"));
+					make_atom(&tmp, new_atom(q->pl, "sha256"));
 					unify(q, arg, arg_ctx, &tmp, q->st.curr_frame);
 					is_sha384 = is_sha512 = false;
 					is_sha256 = true;
@@ -5786,14 +5786,17 @@ static bool fn_base64_3(query *q)
 	return throw_error(q, p1, p1_ctx, "instantiation_error", "atom");
 }
 
-static char *url_encode(const char *src, int len, char *dstbuf)
+char *url_encode(const char *src, int len, char *dstbuf)
 {
 	char *dst = dstbuf;
 
 	// As per RFC3986 (2005)
 
 	while (len-- > 0) {
-		if (!isalnum(*src) && (*src != '-') && (*src != '_') && (*src != '.') && (*src != '~'))
+		if (*src == ' ') {
+			*dst++ = '+';
+			src++;
+		} else if (!isalnum(*src) && (*src != '-') && (*src != '_') && (*src != '.') && (*src != '~'))
 			dst += sprintf(dst, "%%%02X", *src++);
 		else
 			*dst++ = *src++;
@@ -6398,17 +6401,17 @@ static bool fn_sys_legacy_predicate_property_2(query *q)
 		if (evaluable)
 			return false;
 
-		make_atom(&tmp, index_from_pool(q->pl, "built_in"));
+		make_atom(&tmp, new_atom(q->pl, "built_in"));
 
 		if (unify(q, p2, p2_ctx, &tmp, q->st.curr_frame))
 			return true;
 
-		make_atom(&tmp, index_from_pool(q->pl, "static"));
+		make_atom(&tmp, new_atom(q->pl, "static"));
 
 		if (unify(q, p2, p2_ctx, &tmp, q->st.curr_frame))
 			return true;
 
-		make_atom(&tmp, index_from_pool(q->pl, "dynamic"));
+		make_atom(&tmp, new_atom(q->pl, "dynamic"));
 
 		if (unify(q, p2, p2_ctx, &tmp, q->st.curr_frame))
 			return false;
@@ -6422,58 +6425,58 @@ static bool fn_sys_legacy_predicate_property_2(query *q)
 		return false;
 
 	if (!pr->is_dynamic && !is_var(p2)) {
-		make_atom(&tmp, index_from_pool(q->pl, "built_in"));
+		make_atom(&tmp, new_atom(q->pl, "built_in"));
 
 		if (unify(q, p2, p2_ctx, &tmp, q->st.curr_frame))
 			return true;
 	}
 
 	if (!pr->is_dynamic) {
-		make_atom(&tmp, index_from_pool(q->pl, "static"));
+		make_atom(&tmp, new_atom(q->pl, "static"));
 
 		if (unify(q, p2, p2_ctx, &tmp, q->st.curr_frame))
 			return true;
 	}
 
 	if (pr->is_dynamic) {
-		make_atom(&tmp, index_from_pool(q->pl, "dynamic"));
+		make_atom(&tmp, new_atom(q->pl, "dynamic"));
 
 		if (unify(q, p2, p2_ctx, &tmp, q->st.curr_frame))
 			return true;
 	}
 
 	if (pr->is_multifile) {
-		make_atom(&tmp, index_from_pool(q->pl, "multifile"));
+		make_atom(&tmp, new_atom(q->pl, "multifile"));
 
 		if (unify(q, p2, p2_ctx, &tmp, q->st.curr_frame))
 			return true;
 	}
 
 	if (pr->is_public) {
-		make_atom(&tmp, index_from_pool(q->pl, "public"));
+		make_atom(&tmp, new_atom(q->pl, "public"));
 
 		if (unify(q, p2, p2_ctx, &tmp, q->st.curr_frame))
 			return true;
 	}
 
 	if (pr->is_public) {
-		make_atom(&tmp, index_from_pool(q->pl, "exported"));
+		make_atom(&tmp, new_atom(q->pl, "exported"));
 
 		if (unify(q, p2, p2_ctx, &tmp, q->st.curr_frame))
 			return true;
 	}
 
-	make_atom(&tmp, index_from_pool(q->pl, "static"));
+	make_atom(&tmp, new_atom(q->pl, "static"));
 
 	if (unify(q, p2, p2_ctx, &tmp, q->st.curr_frame))
 		return true;
 
-	make_atom(&tmp, index_from_pool(q->pl, "meta_predicate"));
+	make_atom(&tmp, new_atom(q->pl, "meta_predicate"));
 
 	if (unify(q, p2, p2_ctx, &tmp, q->st.curr_frame))
 		return true;
 
-	make_atom(&tmp, index_from_pool(q->pl, "visible"));
+	make_atom(&tmp, new_atom(q->pl, "visible"));
 
 	if (unify(q, p2, p2_ctx, &tmp, q->st.curr_frame))
 		return true;
@@ -6499,22 +6502,22 @@ static bool fn_sys_legacy_evaluable_property_2(query *q)
 		if (!evaluable)
 			return false;
 
-		make_atom(&tmp, index_from_pool(q->pl, "built_in"));
+		make_atom(&tmp, new_atom(q->pl, "built_in"));
 
 		if (unify(q, p2, p2_ctx, &tmp, q->st.curr_frame))
 			return true;
 
-		make_atom(&tmp, index_from_pool(q->pl, "static"));
+		make_atom(&tmp, new_atom(q->pl, "static"));
 
 		if (unify(q, p2, p2_ctx, &tmp, q->st.curr_frame))
 			return true;
 
-		make_atom(&tmp, index_from_pool(q->pl, "dynamic"));
+		make_atom(&tmp, new_atom(q->pl, "dynamic"));
 
 		if (unify(q, p2, p2_ctx, &tmp, q->st.curr_frame))
 			return false;
 
-		make_atom(&tmp, index_from_pool(q->pl, "foreign"));
+		make_atom(&tmp, new_atom(q->pl, "foreign"));
 
 		if (unify(q, p2, p2_ctx, &tmp, q->st.curr_frame))
 			return false;
@@ -6872,7 +6875,7 @@ static bool fn_sys_list_attributed_1(query *q)
 			continue;
 
 		cell v;
-		make_ref(&v, index_from_pool(q->pl, p->vartab.var_name[i]), i, q->st.curr_frame);
+		make_ref(&v, new_atom(q->pl, p->vartab.var_name[i]), i, q->st.curr_frame);
 
 		if (first) {
 			allocate_list(q, &v);
@@ -7247,7 +7250,7 @@ static bool fn_current_module_1(query *q)
 		check_heap_error(push_choice(q));
 		module *m = q->current_m = q->pl->modules;
 		cell tmp;
-		make_atom(&tmp, index_from_pool(q->pl, m->name));
+		make_atom(&tmp, new_atom(q->pl, m->name));
 		return unify(q, p1, p1_ctx, &tmp, q->st.curr_frame);
 	}
 
@@ -7261,7 +7264,7 @@ static bool fn_current_module_1(query *q)
 
 	check_heap_error(push_choice(q));
 	cell tmp;
-	make_atom(&tmp, index_from_pool(q->pl, m->name));
+	make_atom(&tmp, new_atom(q->pl, m->name));
 	return unify(q, p1, p1_ctx, &tmp, q->st.curr_frame);
 }
 
@@ -7296,7 +7299,7 @@ static bool fn_attribute_3(query *q)
 	while (m) {
 		if ((arity == m->arity) && !strcmp(name, m->name)) {
 			cell tmp;
-			make_atom(&tmp, index_from_pool(q->pl, m->orig->name));
+			make_atom(&tmp, new_atom(q->pl, m->orig->name));
 			return unify(q, p1, p1_ctx, &tmp, q->st.curr_frame);
 		}
 
@@ -7304,7 +7307,7 @@ static bool fn_attribute_3(query *q)
 	}
 
 	cell tmp;
-	make_atom(&tmp, index_from_pool(q->pl, q->st.m->name));
+	make_atom(&tmp, new_atom(q->pl, q->st.m->name));
 	return unify(q, p1, p1_ctx, &tmp, q->st.curr_frame);
 }
 
@@ -7317,7 +7320,7 @@ static bool fn_prolog_load_context_2(query *q)
 		return false;
 
 	cell tmp;
-	make_atom(&tmp, index_from_pool(q->pl, q->st.prev_m->name));
+	make_atom(&tmp, new_atom(q->pl, q->st.prev_m->name));
 	return unify(q, p2, p2_ctx, &tmp, q->st.curr_frame);
 }
 
@@ -7327,7 +7330,7 @@ static bool fn_module_1(query *q)
 
 	if (is_var(p1)) {
 		cell tmp;
-		make_atom(&tmp, index_from_pool(q->pl, q->st.m->name));
+		make_atom(&tmp, new_atom(q->pl, q->st.m->name));
 		return unify(q, p1, p1_ctx, &tmp, q->st.curr_frame);
 	}
 
@@ -8004,7 +8007,7 @@ static void load_properties(module *m)
 static void load_flags(query *q)
 {
 	cell tmp;
-	make_atom(&tmp, index_from_pool(q->pl, "$current_prolog_flag"));
+	make_atom(&tmp, new_atom(q->pl, "$current_prolog_flag"));
 	tmp.arity = 2;
 
 	if (do_abolish(q, &tmp, &tmp, false) != true)
diff --git a/src/prolog.c b/src/prolog.c
index 21628d9eb..f8ec9a775 100644
--- a/src/prolog.c
+++ b/src/prolog.c
@@ -45,7 +45,7 @@ bool is_multifile_in_db(prolog *pl, const char *mod, const char *name, unsigned
 
 	cell tmp = (cell){0};
 	tmp.tag = TAG_INTERNED;
-	tmp.val_off = index_from_pool(m->pl, name);
+	tmp.val_off = new_atom(m->pl, name);
 	if (tmp.val_off == ERR_IDX) return false;
 	tmp.arity = arity;
 	predicate *pr = find_predicate(m, &tmp);
@@ -77,7 +77,7 @@ static pl_idx add_to_pool(prolog *pl, const char *name)
 	return (pl_idx)offset;
 }
 
-pl_idx index_from_pool(prolog *pl, const char *name)
+pl_idx new_atom(prolog *pl, const char *name)
 {
 	const void *val;
 
@@ -399,61 +399,61 @@ static bool g_init(prolog *pl)
 	CHECK_SENTINEL(pl->symtab = sl_create((void*)fake_strcmp, (void*)keyfree, NULL), NULL);
 	sl_allow_dups(pl->symtab, false);
 
-	CHECK_SENTINEL(index_from_pool(pl, "dummy"), ERR_IDX);
-	CHECK_SENTINEL(g_false_s = index_from_pool(pl, "false"), ERR_IDX);
-	CHECK_SENTINEL(g_true_s = index_from_pool(pl, "true"), ERR_IDX);
-	CHECK_SENTINEL(g_at_s = index_from_pool(pl, "@"), ERR_IDX);
-	CHECK_SENTINEL(g_conjunction_s = index_from_pool(pl, ","), ERR_IDX);
-	CHECK_SENTINEL(g_disjunction_s = index_from_pool(pl, ";"), ERR_IDX);
-	CHECK_SENTINEL(g_if_then_s = index_from_pool(pl, "->"), ERR_IDX);
-	CHECK_SENTINEL(g_soft_cut_s = index_from_pool(pl, "*->"), ERR_IDX);
-	CHECK_SENTINEL(g_negation_s = index_from_pool(pl, "\\+"), ERR_IDX);
-	CHECK_SENTINEL(g_dot_s = index_from_pool(pl, "."), ERR_IDX);
-	CHECK_SENTINEL(g_plus_s = index_from_pool(pl, "+"), ERR_IDX);
-	CHECK_SENTINEL(g_minus_s = index_from_pool(pl, "-"), ERR_IDX);
-	CHECK_SENTINEL(g_empty_s = index_from_pool(pl, ""), ERR_IDX);
-	CHECK_SENTINEL(g_anon_s = index_from_pool(pl, "_"), ERR_IDX);
-	CHECK_SENTINEL(g_dcg_s = index_from_pool(pl, "-->"), ERR_IDX);
-	CHECK_SENTINEL(g_call_s = index_from_pool(pl, "call"), ERR_IDX);
-	CHECK_SENTINEL(g_syscall_s = index_from_pool(pl, "$call"), ERR_IDX);
-	CHECK_SENTINEL(g_braces_s = index_from_pool(pl, "braces"), ERR_IDX);
-	CHECK_SENTINEL(g_unify_s = index_from_pool(pl, "="), ERR_IDX);
-	CHECK_SENTINEL(g_on_s = index_from_pool(pl, "on"), ERR_IDX);
-	CHECK_SENTINEL(g_off_s = index_from_pool(pl, "off"), ERR_IDX);
-	CHECK_SENTINEL(g_cut_s = index_from_pool(pl, "!"), ERR_IDX);
-	CHECK_SENTINEL(g_nil_s = index_from_pool(pl, "[]"), ERR_IDX);
-	CHECK_SENTINEL(g_braces_s = index_from_pool(pl, "{}"), ERR_IDX);
-	CHECK_SENTINEL(g_fail_s = index_from_pool(pl, "fail"), ERR_IDX);
-	CHECK_SENTINEL(g_neck_s = index_from_pool(pl, ":-"), ERR_IDX);
-	CHECK_SENTINEL(g_eof_s = index_from_pool(pl, "end_of_file"), ERR_IDX);
-	CHECK_SENTINEL(g_lt_s = index_from_pool(pl, "<"), ERR_IDX);
-	CHECK_SENTINEL(g_gt_s = index_from_pool(pl, ">"), ERR_IDX);
-	CHECK_SENTINEL(g_eq_s = index_from_pool(pl, "="), ERR_IDX);
-	CHECK_SENTINEL(g_once_s = index_from_pool(pl, "once"), ERR_IDX);
-	CHECK_SENTINEL(g_throw_s = index_from_pool(pl, "throw"), ERR_IDX);
-	CHECK_SENTINEL(g_error_s = index_from_pool(pl, "error"), ERR_IDX);
-	CHECK_SENTINEL(g_slash_s = index_from_pool(pl, "/"), ERR_IDX);
-	CHECK_SENTINEL(g_goal_expansion_s = index_from_pool(pl, "goal_expansion"), ERR_IDX);
-	CHECK_SENTINEL(g_term_expansion_s = index_from_pool(pl, "term_expansion"), ERR_IDX);
-	CHECK_SENTINEL(g_tm_s = index_from_pool(pl, "tm"), ERR_IDX);
-	CHECK_SENTINEL(g_float_s = index_from_pool(pl, "float"), ERR_IDX);
-
-	CHECK_SENTINEL(g_sys_elapsed_s = index_from_pool(pl, "$elapsed"), ERR_IDX);
-	CHECK_SENTINEL(g_sys_queue_s = index_from_pool(pl, "$queue"), ERR_IDX);
-	CHECK_SENTINEL(g_sys_var_s = index_from_pool(pl, "$VAR"), ERR_IDX);
-	CHECK_SENTINEL(g_sys_stream_property_s = index_from_pool(pl, "$stream_property"), ERR_IDX);
-	CHECK_SENTINEL(g_post_unify_hook_s = index_from_pool(pl, "$post_unify_hook"), ERR_IDX);
-	CHECK_SENTINEL(g_sys_record_key_s = index_from_pool(pl, "$record_key"), ERR_IDX);
-	CHECK_SENTINEL(g_sys_ne_s = index_from_pool(pl, "$ne"), ERR_IDX);
-	CHECK_SENTINEL(g_sys_incr_s = index_from_pool(pl, "$incr"), ERR_IDX);
-	CHECK_SENTINEL(g_sys_block_catcher_s = index_from_pool(pl, "$block_catcher"), ERR_IDX);
-	CHECK_SENTINEL(g_sys_drop_barrier_s = index_from_pool(pl, "$drop_barrier"), ERR_IDX);
-	CHECK_SENTINEL(g_sys_cleanup_if_det_s = index_from_pool(pl, "$cleanup_if_det"), ERR_IDX);
-	CHECK_SENTINEL(g_sys_cut_if_det_s = index_from_pool(pl, "$cut_if_det"), ERR_IDX);
-	CHECK_SENTINEL(g_sys_table_s = index_from_pool(pl, "$table"), ERR_IDX);
-	CHECK_SENTINEL(g_as_s = index_from_pool(pl, "as"), ERR_IDX);
-	CHECK_SENTINEL(g_colon_s = index_from_pool(pl, ":"), ERR_IDX);
-	CHECK_SENTINEL(g_caret_s = index_from_pool(pl, "^"), ERR_IDX);
+	CHECK_SENTINEL(new_atom(pl, "dummy"), ERR_IDX);
+	CHECK_SENTINEL(g_false_s = new_atom(pl, "false"), ERR_IDX);
+	CHECK_SENTINEL(g_true_s = new_atom(pl, "true"), ERR_IDX);
+	CHECK_SENTINEL(g_at_s = new_atom(pl, "@"), ERR_IDX);
+	CHECK_SENTINEL(g_conjunction_s = new_atom(pl, ","), ERR_IDX);
+	CHECK_SENTINEL(g_disjunction_s = new_atom(pl, ";"), ERR_IDX);
+	CHECK_SENTINEL(g_if_then_s = new_atom(pl, "->"), ERR_IDX);
+	CHECK_SENTINEL(g_soft_cut_s = new_atom(pl, "*->"), ERR_IDX);
+	CHECK_SENTINEL(g_negation_s = new_atom(pl, "\\+"), ERR_IDX);
+	CHECK_SENTINEL(g_dot_s = new_atom(pl, "."), ERR_IDX);
+	CHECK_SENTINEL(g_plus_s = new_atom(pl, "+"), ERR_IDX);
+	CHECK_SENTINEL(g_minus_s = new_atom(pl, "-"), ERR_IDX);
+	CHECK_SENTINEL(g_empty_s = new_atom(pl, ""), ERR_IDX);
+	CHECK_SENTINEL(g_anon_s = new_atom(pl, "_"), ERR_IDX);
+	CHECK_SENTINEL(g_dcg_s = new_atom(pl, "-->"), ERR_IDX);
+	CHECK_SENTINEL(g_call_s = new_atom(pl, "call"), ERR_IDX);
+	CHECK_SENTINEL(g_syscall_s = new_atom(pl, "$call"), ERR_IDX);
+	CHECK_SENTINEL(g_braces_s = new_atom(pl, "braces"), ERR_IDX);
+	CHECK_SENTINEL(g_unify_s = new_atom(pl, "="), ERR_IDX);
+	CHECK_SENTINEL(g_on_s = new_atom(pl, "on"), ERR_IDX);
+	CHECK_SENTINEL(g_off_s = new_atom(pl, "off"), ERR_IDX);
+	CHECK_SENTINEL(g_cut_s = new_atom(pl, "!"), ERR_IDX);
+	CHECK_SENTINEL(g_nil_s = new_atom(pl, "[]"), ERR_IDX);
+	CHECK_SENTINEL(g_braces_s = new_atom(pl, "{}"), ERR_IDX);
+	CHECK_SENTINEL(g_fail_s = new_atom(pl, "fail"), ERR_IDX);
+	CHECK_SENTINEL(g_neck_s = new_atom(pl, ":-"), ERR_IDX);
+	CHECK_SENTINEL(g_eof_s = new_atom(pl, "end_of_file"), ERR_IDX);
+	CHECK_SENTINEL(g_lt_s = new_atom(pl, "<"), ERR_IDX);
+	CHECK_SENTINEL(g_gt_s = new_atom(pl, ">"), ERR_IDX);
+	CHECK_SENTINEL(g_eq_s = new_atom(pl, "="), ERR_IDX);
+	CHECK_SENTINEL(g_once_s = new_atom(pl, "once"), ERR_IDX);
+	CHECK_SENTINEL(g_throw_s = new_atom(pl, "throw"), ERR_IDX);
+	CHECK_SENTINEL(g_error_s = new_atom(pl, "error"), ERR_IDX);
+	CHECK_SENTINEL(g_slash_s = new_atom(pl, "/"), ERR_IDX);
+	CHECK_SENTINEL(g_goal_expansion_s = new_atom(pl, "goal_expansion"), ERR_IDX);
+	CHECK_SENTINEL(g_term_expansion_s = new_atom(pl, "term_expansion"), ERR_IDX);
+	CHECK_SENTINEL(g_tm_s = new_atom(pl, "tm"), ERR_IDX);
+	CHECK_SENTINEL(g_float_s = new_atom(pl, "float"), ERR_IDX);
+
+	CHECK_SENTINEL(g_sys_elapsed_s = new_atom(pl, "$elapsed"), ERR_IDX);
+	CHECK_SENTINEL(g_sys_queue_s = new_atom(pl, "$queue"), ERR_IDX);
+	CHECK_SENTINEL(g_sys_var_s = new_atom(pl, "$VAR"), ERR_IDX);
+	CHECK_SENTINEL(g_sys_stream_property_s = new_atom(pl, "$stream_property"), ERR_IDX);
+	CHECK_SENTINEL(g_post_unify_hook_s = new_atom(pl, "$post_unify_hook"), ERR_IDX);
+	CHECK_SENTINEL(g_sys_record_key_s = new_atom(pl, "$record_key"), ERR_IDX);
+	CHECK_SENTINEL(g_sys_ne_s = new_atom(pl, "$ne"), ERR_IDX);
+	CHECK_SENTINEL(g_sys_incr_s = new_atom(pl, "$incr"), ERR_IDX);
+	CHECK_SENTINEL(g_sys_block_catcher_s = new_atom(pl, "$block_catcher"), ERR_IDX);
+	CHECK_SENTINEL(g_sys_drop_barrier_s = new_atom(pl, "$drop_barrier"), ERR_IDX);
+	CHECK_SENTINEL(g_sys_cleanup_if_det_s = new_atom(pl, "$cleanup_if_det"), ERR_IDX);
+	CHECK_SENTINEL(g_sys_cut_if_det_s = new_atom(pl, "$cut_if_det"), ERR_IDX);
+	CHECK_SENTINEL(g_sys_table_s = new_atom(pl, "$table"), ERR_IDX);
+	CHECK_SENTINEL(g_as_s = new_atom(pl, "as"), ERR_IDX);
+	CHECK_SENTINEL(g_colon_s = new_atom(pl, ":"), ERR_IDX);
+	CHECK_SENTINEL(g_caret_s = new_atom(pl, "^"), ERR_IDX);
 
 	return error;
 }
diff --git a/src/prolog.h b/src/prolog.h
index 731f84f98..bf5284f93 100644
--- a/src/prolog.h
+++ b/src/prolog.h
@@ -6,7 +6,7 @@ builtins *get_builtin(prolog *pl, const char *name, size_t len, unsigned arity,
 builtins *get_help(prolog *pl, const char *name, unsigned arity, bool *found, bool *evaluable);
 module *find_module(prolog *pl, const char *name);
 module *find_next_module(prolog *pl, module *m);
-pl_idx index_from_pool(prolog *pl, const char *name);
+pl_idx new_atom(prolog *pl, const char *name);
 bool is_multifile_in_db(prolog *pl, const char *mod, const char *name, unsigned arity);
 void load_builtins(prolog *pl);
 void uuid_gen(prolog *pl, uuid *u);
diff --git a/src/query.c b/src/query.c
index 470ab6b90..a2d78f85b 100644
--- a/src/query.c
+++ b/src/query.c
@@ -471,7 +471,7 @@ static bool expand_meta_predicate(query *q, predicate *pr)
 		else if (m->val_off == g_colon_s) {
 			make_struct(tmp, g_colon_s, NULL, 2, 1+k->nbr_cells);
 			SET_OP(tmp, OP_XFY); tmp++;
-			make_atom(tmp++, index_from_pool(q->pl, pr->m->name));
+			make_atom(tmp++, new_atom(q->pl, pr->m->name));
 		}
 
 		tmp += safe_copy_cells(tmp, k, k->nbr_cells);
diff --git a/src/query.h b/src/query.h
index a03dd1a0b..a81ac62c6 100644
--- a/src/query.h
+++ b/src/query.h
@@ -23,6 +23,8 @@ bool do_read_term(query *q, stream *str, cell *p1, pl_idx p1_ctx, cell *p2, pl_i
 bool do_yield(query *q, int msecs);
 void do_yield_at(query *q, unsigned int time_in_ms);
 
+char *url_encode(const char *src, int len, char *dstbuf);
+char *url_decode(const char *src, char *dstbuf);
 cell *do_term_variables(query *q, cell *p1, pl_idx p1_ctx);
 bool query_redo(query *q);
 bool has_next_key(query *q);
diff --git a/src/streams.c b/src/streams.c
index 9e0fc637d..647c2cea9 100644
--- a/src/streams.c
+++ b/src/streams.c
@@ -726,13 +726,13 @@ static bool do_stream_property(query *q)
 		cell tmp;
 
 		if (str->eof_action == eof_action_eof_code)
-			make_atom(&tmp, index_from_pool(q->pl, "eof_code"));
+			make_atom(&tmp, new_atom(q->pl, "eof_code"));
 		else if (str->eof_action == eof_action_error)
-			make_atom(&tmp, index_from_pool(q->pl, "error"));
+			make_atom(&tmp, new_atom(q->pl, "error"));
 		else if (str->eof_action == eof_action_reset)
-			make_atom(&tmp, index_from_pool(q->pl, "reset"));
+			make_atom(&tmp, new_atom(q->pl, "reset"));
 		else
-			make_atom(&tmp, index_from_pool(q->pl, "none"));
+			make_atom(&tmp, new_atom(q->pl, "none"));
 
 		return unify(q, c, c_ctx, &tmp, q->st.curr_frame);
 	}
@@ -764,11 +764,11 @@ static bool do_stream_property(query *q)
 		cell tmp;
 
 		if (str->at_end_of_file)
-			make_atom(&tmp, index_from_pool(q->pl, "past"));
+			make_atom(&tmp, new_atom(q->pl, "past"));
 		else if (at_end_of_file)
-			make_atom(&tmp, index_from_pool(q->pl, "at"));
+			make_atom(&tmp, new_atom(q->pl, "at"));
 		else
-			make_atom(&tmp, index_from_pool(q->pl, "not"));
+			make_atom(&tmp, new_atom(q->pl, "not"));
 
 		return unify(q, c, c_ctx, &tmp, q->st.curr_frame);
 	}
@@ -6195,6 +6195,275 @@ static bool fn_accept_2(query *q)
 	return unify(q, p1, p1_ctx, &tmp, q->st.curr_frame);
 }
 
+static bool do_parse_parts(query *q, bool full)
+{
+	GET_FIRST_ARG(p1,atom_or_var);
+	GET_NEXT_ARG(p2,iso_list);
+	char protocol[256], host[1024], path[8192], search[8192], fragment[8192];
+	protocol[0] = host[0] = path[0] = search[0] = fragment[0] = '\0';
+	int port = 0;
+	LIST_HANDLER(p2);
+
+	while (is_iso_list(p2)) {
+		cell *h = LIST_HEAD(p2);
+		h = deref(q, h, p2_ctx);
+		pl_idx h_ctx = q->latest_ctx;
+
+		if (!strcmp(C_STR(q, h), "protocol")) {
+			if (!is_atom(h+1))
+				return throw_error(q, h+1, p2_ctx, "type_error", "atom");
+
+			sprintf(protocol, C_STR(q, h+1));
+		} else if (!strcmp(C_STR(q, h), "host")) {
+			if (!is_atom(h+1))
+				return throw_error(q, h+1, p2_ctx, "type_error", "atom");
+
+			sprintf(host, C_STR(q, h+1));
+		} else if (!strcmp(C_STR(q, h), "port")) {
+			if (!is_smallint(h+1))
+				return throw_error(q, h+1, p2_ctx, "type_error", "integer");
+
+			port = get_smallint(h+1);
+		} else if (!strcmp(C_STR(q, h), "path")) {
+			if (!is_atom(h+1))
+				return throw_error(q, h+1, p2_ctx, "type_error", "atom");
+
+			sprintf(path, C_STR(q, h+1));
+		} else if (!strcmp(C_STR(q, h), "search")) {
+			cell *h1 = h + 1;
+			h1 = deref(q, h1, h_ctx);
+			pl_idx h1_ctx = q->latest_ctx;
+
+			if (!is_iso_list(h1))
+				return throw_error(q, h1, h_ctx, "type_error", "list");
+
+			char *dst = search;
+			LIST_HANDLER(h1);
+
+			while (is_iso_list(h1)) {
+				cell *c = LIST_HEAD(h1);
+				c = deref(q, c, h1_ctx);
+
+				if (!is_structure(c))
+					return throw_error(q, c, h1_ctx, "type_error", "compound");
+
+				if (!is_atom(c+1))
+					return throw_error(q, c+1, h1_ctx, "type_error", "atom");
+
+				if (!is_atom(c+2))
+					return throw_error(q, c+2, h1_ctx, "type_error", "atom");
+
+				size_t len2 = C_STRLEN(q, c+2);
+				char *dstbuf2 = malloc(len2+1);
+				check_heap_error(dstbuf2);
+				url_encode(C_STR(q, c+2), len2, dstbuf2);
+				dst += sprintf(dst, "%s=%s", C_STR(q, c+1), dstbuf2);
+				free(dstbuf2);
+
+				h1 = LIST_TAIL(h1);
+				h1 = deref(q, h1, h1_ctx);
+				h1_ctx = q->latest_ctx;
+
+				if (!is_nil(h1))
+					dst += sprintf(dst, "&");
+			}
+		} else if (!strcmp(C_STR(q, h), "fragment")) {
+			if (!is_atom(h+1))
+				return throw_error(q, h+1, p2_ctx, "type_error", "atom");
+
+			sprintf(fragment, C_STR(q, h+1));
+		}
+
+		p2 = LIST_TAIL(p2);
+		p2 = deref(q, p2, p2_ctx);
+		p2_ctx = q->latest_ctx;
+	}
+
+	SB(pr);
+	SB_sprintf(pr, "%s://%s", protocol, host);
+	if (port) SB_sprintf(pr, "%d", port);
+	if (path[0]) SB_sprintf(pr, "%s", path);
+	if (search[0]) SB_sprintf(pr, "?%s", search);
+	if (fragment[0]) SB_sprintf(pr, "#%s", fragment);
+	cell tmp;
+	make_cstring(&tmp,  SB_cstr(pr));
+	return unify(q, p1, p1_ctx, &tmp, q->st.curr_frame);
+}
+
+static bool do_parse_url(query *q, bool full)
+{
+	GET_FIRST_ARG(p1,atom);
+	GET_NEXT_ARG(p2,iso_list_or_var);
+
+	const char *src = C_STR(q, p1);
+	char protocol[256], host[1024], path[8192], search[8192], fragment[8192];
+	protocol[0] = host[0] = path[0] = search[0] = fragment[0] = '\0';
+
+	if (full)
+		sscanf(src, "%255[^:\r\n]://%1023[^/\r\n]%8191[^?\r\n]?%8191[^#\r\n]#%8191[^\r\n]", protocol, host, path, search, fragment);
+	else
+		sscanf(src, "%8191[^?\r\n]?%8191[^#\r\n]#%8191[^\r\n]", path, search, fragment);
+
+	protocol[255] = host[1023] = path[8191] = search[8191] = fragment[8191] = '\0';
+	char *dstbuf;
+	size_t len;
+	cell tmp[3];
+
+	if (search[0]) {
+		allocate_list(q, tmp);
+		char key[8192], search2[8192];
+		key[0] = search2[0] = '\0';
+		char *src2 = search, *dst2 = key;
+		bool first = true;
+
+		while (*src2) {
+			if (*src2 == '=') {
+				src2++;
+				dst2 = search2;
+				*dst2 = '\0';
+			} else if (*src2 == '&') {
+				make_struct(tmp, new_atom(q->pl, "="), NULL, 2, 2);
+				SET_OP(tmp, OP_YFX);
+
+				len = strlen(key);
+				dstbuf = malloc(len+1);
+				check_heap_error(dstbuf);
+				url_decode(key, dstbuf);
+				make_cstring(tmp+1, dstbuf);
+				free(dstbuf);
+
+				len = strlen(search2);
+				dstbuf = malloc(len+1);
+				check_heap_error(dstbuf);
+				url_decode(search2, dstbuf);
+				make_cstring(tmp+2, dstbuf);
+				free(dstbuf);
+
+				if (first) {
+					allocate_list(q, tmp);
+					first = false;
+				} else
+					append_list(q, tmp);
+
+				src2++;
+				dst2 = key;
+				*dst2 = '\0';
+			}
+
+			*dst2++ = *src2++;
+			*dst2 = '\0';
+		}
+
+		make_struct(tmp, new_atom(q->pl, "="), NULL, 2, 2);
+		SET_OP(tmp, OP_YFX);
+
+		len = strlen(key);
+		dstbuf = malloc(len+1);
+		check_heap_error(dstbuf);
+		url_decode(key, dstbuf);
+		make_cstring(tmp+1, dstbuf);
+		free(dstbuf);
+
+		len = strlen(search2);
+		dstbuf = malloc(len+1);
+		check_heap_error(dstbuf);
+		url_decode(search2, dstbuf);
+		make_cstring(tmp+2, dstbuf);
+		free(dstbuf);
+		append_list(q, tmp);
+
+		cell *l = end_list(q);
+		cell *tmp2 = alloc_on_heap(q, 1 + l->nbr_cells);
+		make_struct(tmp2, new_atom(q->pl, "search"), NULL, 1, l->nbr_cells);
+		safe_copy_cells(tmp2+1, l, l->nbr_cells);
+		allocate_list(q, tmp2);
+	}
+
+	if (protocol[0]) {
+		make_struct(tmp, new_atom(q->pl, "protocol"), NULL, 1, 1);
+		make_cstring(tmp+1, protocol);
+
+		if (search[0])
+			append_list(q, tmp);
+		else
+			allocate_list(q, tmp);
+	}
+
+	if (host[0]) {
+		char host2[256]; host2[0] = '\0';
+		int port = 0;
+		sscanf(host, "%255[^:]:%d", host2, &port);
+		host2[255] = '\0';
+
+		make_struct(tmp, new_atom(q->pl, "host"), NULL, 1, 1);
+		make_cstring(tmp+1, host2);
+		append_list(q, tmp);
+
+		if (port) {
+			make_struct(tmp, new_atom(q->pl, "port"), NULL, 1, 1);
+			make_int(tmp+1, port);
+			append_list(q, tmp);
+		}
+	}
+
+	if (!path[0])
+		strcpy(path, "/");
+
+	if (path[0]) {
+		len = strlen(path);
+		dstbuf = malloc(len+1);
+		check_heap_error(dstbuf);
+		url_decode(path, dstbuf);
+		src = dstbuf;
+		make_struct(tmp, new_atom(q->pl, "path"), NULL, 1, 1);
+		make_cstring(tmp+1, path);
+		append_list(q, tmp);
+		free(dstbuf);
+	}
+
+	if (fragment[0]) {
+		len = strlen(fragment);
+		dstbuf = malloc(len+1);
+		check_heap_error(dstbuf);
+		url_decode(path, dstbuf);
+		src = dstbuf;
+		make_struct(tmp, new_atom(q->pl, "fragment"), NULL, 1, 1);
+		make_cstring(tmp+1, fragment);
+		append_list(q, tmp);
+		free(dstbuf);
+	}
+
+	return unify(q, p2, p2_ctx, end_list(q), q->st.curr_frame);
+}
+
+static bool fn_parse_url_2(query *q)
+{
+	GET_FIRST_ARG(p1,atom_or_var);
+	GET_NEXT_ARG(p2,iso_list_or_var);
+
+	if (is_var(p1) && is_var(p2))
+		return throw_error2(q, p1, p1_ctx, "uninstantiation_error", "not_sufficiently_instantiated", p2);
+
+	if (is_var(p2))
+		return do_parse_url(q, true);
+	else
+		return do_parse_parts(q, true);
+}
+
+static bool fn_parse_location_2(query *q)
+{
+	GET_FIRST_ARG(p1,atom_or_var);
+	GET_NEXT_ARG(p2,iso_list_or_var);
+
+	if (is_var(p1) && is_var(p2))
+		return throw_error2(q, p1, p1_ctx, "uninstantiation_error", "not_sufficiently_instantiated", p2);
+
+	if (is_var(p2))
+		return do_parse_url(q, false);
+	else
+		return do_parse_parts(q, false);
+}
+
 static bool fn_client_5(query *q)
 {
 	GET_FIRST_ARG(p1,atom);
@@ -7343,6 +7612,8 @@ builtins g_files_bifs[] =
 	{"read_line_to_string", 2, fn_read_line_to_string_2, "+stream,-character_list", false, false, BLAH},
 	{"read_file_to_string", 3, fn_read_file_to_string_3, "+atom,-string,+options", false, false, BLAH},
 
+	{"parse_location", 2, fn_parse_location_2, "?atom,?list", false, false, BLAH},
+	{"parse_url", 2, fn_parse_url_2, "?atom,?list", false, false, BLAH},
 	{"client", 5, fn_client_5, "+atom,-atom,-atom,-atom,+list", false, false, BLAH},
 	{"server", 3, fn_server_3, "+atom,--stream,+list", false, false, BLAH},
 	{"accept", 2, fn_accept_2, "+stream,--stream", false, false, BLAH},
diff --git a/src/toplevel.c b/src/toplevel.c
index 9208dabb7..35dab736a 100644
--- a/src/toplevel.c
+++ b/src/toplevel.c
@@ -509,7 +509,7 @@ void dump_vars(query *q, bool partial)
 		q->variable_names_ctx = 0;
 		q->tab_idx = 0;
 		cell p1;
-		make_atom(&p1, index_from_pool(q->pl, "dump_attvars"));
+		make_atom(&p1, new_atom(q->pl, "dump_attvars"));
 		cell *tmp = prepare_call(q, false, &p1, q->st.curr_frame, 1);
 		pl_idx nbr_cells = NOPREFIX_LEN + p1.nbr_cells;
 		make_end(tmp+nbr_cells);