diff --git a/src/oberon.c b/src/oberon.c
index 3b4a3747b904d0dbef91c4bb3f2ee11960e19679..e4b9157d151cafa6075c86bbc1a07ebf2e845bef 100644 (file)
--- a/src/oberon.c
+++ b/src/oberon.c
RBRACE,
DOTDOT,
CASE,
- BAR
+ BAR,
+ WITH
};
// =======================================================================
{
ctx -> token = CASE;
}
+ else if(strcmp(ident, "WITH") == 0)
+ {
+ ctx -> token = WITH;
+ }
}
static void
}
static oberon_expr_t *
-oberon_designator(oberon_context_t * ctx)
+oberon_qualident_expr(oberon_context_t * ctx)
{
- char * name;
oberon_object_t * var;
oberon_expr_t * expr;
oberon_error(ctx, "invalid designator");
break;
}
+
expr -> item.var = var;
+ return expr;
+}
+
+static oberon_expr_t *
+oberon_designator(oberon_context_t * ctx)
+{
+ char * name;
+ oberon_expr_t * expr;
+
+ expr = oberon_qualident_expr(ctx);
+
while(expr -> result -> class != OBERON_TYPE_PROCEDURE && ISSELECTOR(ctx -> token))
{
switch(ctx -> token)
oberon_assert_token(ctx, END);
}
+static void
+oberon_with_guard_do(oberon_context_t * ctx, gen_label_t * end)
+{
+ oberon_expr_t * val;
+ oberon_expr_t * var;
+ oberon_expr_t * type;
+ oberon_expr_t * cond;
+ oberon_expr_t * cast;
+ oberon_type_t * old_type;
+ gen_var_t * old_var;
+ gen_label_t * this_end;
+
+ this_end = oberon_generator_reserve_label(ctx);
+
+ var = oberon_qualident_expr(ctx);
+ oberon_assert_token(ctx, COLON);
+ type = oberon_qualident_expr(ctx);
+ cond = oberon_make_bin_op(ctx, IS, var, type);
+
+ oberon_assert_token(ctx, DO);
+ oberon_generate_branch(ctx, cond, false, this_end);
+
+ /* Сохраняем ссылку во временной переменной */
+ val = oberon_make_temp_var_item(ctx, type -> result);
+ cast = oberno_make_record_cast(ctx, var, type -> result);
+ oberon_assign(ctx, cast, val);
+ /* Подменяем тип у оригинальной переменной */
+ old_type = var -> item.var -> type;
+ var -> item.var -> type = type -> result;
+ /* Подменяем ссылку на переменную */
+ old_var = var -> item.var -> gen_var;
+ var -> item.var -> gen_var = val -> item.var -> gen_var;
+
+ oberon_statement_seq(ctx);
+ oberon_generate_goto(ctx, end);
+ oberon_generate_label(ctx, this_end);
+
+ /* Возвращаем исходное состояние */
+ var -> item.var -> gen_var = old_var;
+ var -> item.var -> type = old_type;
+}
+
+static void
+oberon_with_statement(oberon_context_t * ctx)
+{
+ gen_label_t * end;
+ end = oberon_generator_reserve_label(ctx);
+
+ oberon_assert_token(ctx, WITH);
+ oberon_with_guard_do(ctx, end);
+ while(ctx -> token == BAR)
+ {
+ oberon_assert_token(ctx, BAR);
+ oberon_with_guard_do(ctx, end);
+ }
+
+ if(ctx -> token == ELSE)
+ {
+ oberon_assert_token(ctx, ELSE);
+ oberon_statement_seq(ctx);
+ }
+
+ oberon_generate_label(ctx, end);
+ oberon_assert_token(ctx, END);
+}
+
static void
oberon_statement(oberon_context_t * ctx)
{
{
oberon_case_statement(ctx);
}
+ else if(ctx -> token == WITH)
+ {
+ oberon_with_statement(ctx);
+ }
else if(ctx -> token == RETURN)
{
oberon_assert_token(ctx, RETURN);