darkplaces/gmqcc
0
0
Fork 0
mirror of https://github.com/DarkPlacesEngine/gmqcc.git synced 2025-03-21 18:30:52 +00:00
Code Issues Projects Releases Packages Wiki Activity

handling of operations

Browse source
This commit is contained in:
Wolfgang Bumiller 2012-07-20 15:02:18 +02:00
parent 5d6767f337
commit 7185366ee5
1 changed files with 42 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

43
parser.c
View file

@ -181,7 +181,7 @@ static ast_value *parser_parse_type(parser_t *parser, int basetype, bool *isfunc
typedef struct
{
int etype; /* 0 = expression, others are operators */
size_t etype; /* 0 = expression, others are operators */
ast_expression* out;
} sy_elem;
typedef struct
@ -200,6 +200,18 @@ static sy_elem syexp(ast_expression *v) {
}
static sy_elem syval(ast_value *v) { return syexp((ast_expression*)v); }
static sy_elem syop(const oper_info *op) {
sy_elem e;
e.etype = 1 + (op - operators);
e.out = NULL;
return e;
}
static bool parser_sy_pop(parser_t *parser, shynt *sy)
{
return true;
}
static ast_expression* parser_expression(parser_t *parser)
{
ast_expression *expr = NULL;
@ -258,6 +270,8 @@ static ast_expression* parser_expression(parser_t *parser)
} else {
/* classify the operator */
/* TODO: suffix operators */
const oper_info *op;
const oper_info *olast = NULL;
size_t o;
for (o = 0; o < operator_count; ++o) {
if (!(operators[o].flags & OP_PREFIX) &&
@ -271,6 +285,23 @@ static ast_expression* parser_expression(parser_t *parser)
/* no operator found... must be the end of the statement */
break;
}
/* found an operator */
op = &operators[o];
if (sy.ops_count)
olast = &operators[sy.ops[sy.ops_count-1].etype-1];
while (olast && (
(op->prec < olast->prec) ||
(op->assoc == ASSOC_LEFT && op->prec <= olast->prec) ) )
{
if (!parser_sy_pop(parser, &sy))
goto onerr;
olast = sy.ops_count ? (&operators[sy.ops[sy.ops_count-1].etype-1]) : NULL;
}
if (!shynt_ops_add(&sy, syop(op)))
goto onerr;
}
wantop = false;
parser->lex->flags.noops = true;
@ -280,7 +311,17 @@ static ast_expression* parser_expression(parser_t *parser)
}
}
while (sy.ops_count) {
if (!parser_sy_pop(parser, &sy))
goto onerr;
}
parser->lex->flags.noops = true;
if (!sy.out_count) {
parseerror(parser, "empty expression");
expr = NULL;
} else
expr = sy.out[0].out;
MEM_VECTOR_CLEAR(&sy, out);
MEM_VECTOR_CLEAR(&sy, ops);
return expr;