From b971ddec3a7bb56ac6c9bc094916828283838adf Mon Sep 17 00:00:00 2001
From: Dale Weiler <killfieldengine@gmail.com>
Date: Fri, 8 Mar 2013 08:01:45 +0000
Subject: [PATCH] Implemented concept of enumeration attributes (can be further
extended, but currently only "flag" is implemented as an attribute). An
enumeration with a flag attribute will act as a "flagged enumeration", one
that automatically handles exponentiation of the constants defined inside it,
i.e enum : flag { A, B, C }, A,B,C will equal 2, 4, 8.
---
parser.c | 26 +++++++++++++++++++++++---
tests/enum.qc | 10 ++++++++++
tests/enum.tmpl | 3 +++
3 files changed, 36 insertions(+), 3 deletions(-)
diff --git a/parser.c b/parser.c
index 98c0c9f..bd4f1c1 100644
--- a/parser.c
+++ b/parser.c
@@ -3861,6 +3861,7 @@ static bool parse_statement(parser_t *parser, ast_block *block, ast_expression *
static bool parse_enum(parser_t *parser)
{
+ bool flag = false;
qcfloat num = 0;
ast_value **values = NULL;
ast_value *var = NULL;
@@ -3868,11 +3869,28 @@ static bool parse_enum(parser_t *parser)
ast_expression *old;
- if (!parser_next(parser) || parser->tok != '{') {
- parseerror(parser, "expected `{` after `enum` keyword");
+ if (!parser_next(parser) || (parser->tok != '{' && parser->tok != ':')) {
+ parseerror(parser, "expected `{` or `:` after `enum` keyword");
return false;
}
+ /* enumeration attributes (can add more later) */
+ if (parser->tok == ':') {
+ if (!parser_next(parser) || parser->tok != TOKEN_IDENT || strcmp(parser_tokval(parser), "flag")) {
+ parseerror(parser, "expected `flag` after enumeration attribute ':'");
+ return false;
+ }
+
+ if (!parser_next(parser) || parser->tok != '{') {
+ parseerror(parser, "expected `{` after enum attribute `flag`");
+ return false;
+ }
+
+ /* flagged enumeration start from 1 */
+ num = 1;
+ flag = true;
+ }
+
while (true) {
if (!parser_next(parser) || parser->tok != TOKEN_IDENT) {
if (parser->tok == '}') {
@@ -3896,7 +3914,9 @@ static bool parse_enum(parser_t *parser)
vec_push(values, var);
var->cvq = CV_CONST;
var->hasvalue = true;
- var->constval.vfloat = num++;
+
+ /* for flagged enumerations increment in POTs of TWO */
+ var->constval.vfloat = (flag) ? (num *= 2) : (num ++);
parser_addglobal(parser, var->name, (ast_expression*)var);
diff --git a/tests/enum.qc b/tests/enum.qc
index da08cee..1691661 100644
--- a/tests/enum.qc
+++ b/tests/enum.qc
@@ -27,6 +27,12 @@ enum {
N
};
+enum : flag {
+ F1, /* = 1 << 1 */
+ F2, /* = 1 << 2 */
+ F3 /* = 1 << 3 */
+};
+
void main() {
print(ftos(A), "\n");
print(ftos(B), "\n");
@@ -42,4 +48,8 @@ void main() {
print(ftos(L), "\n");
print(ftos(M), "\n");
print(ftos(N), "\n");
+
+ print(ftos(F1), "\n");
+ print(ftos(F2), "\n");
+ print(ftos(F3), "\n");
};
diff --git a/tests/enum.tmpl b/tests/enum.tmpl
index 28cbd57..c39537a 100644
--- a/tests/enum.tmpl
+++ b/tests/enum.tmpl
@@ -16,3 +16,6 @@ M: 10
M: 11
M: 12
M: 13
+M: 2
+M: 4
+M: 8
--
2.39.5