feat: conditional select

1 files changed, 37 insertions, 0 deletions

diff --git a/src/parser.c b/src/parser.c
index 5379114..b0e049c 100644
--- a/src/parser.c
+++ b/src/parser.c
@@ -721,6 +721,43 @@ static bool parse_statement(struct Parser* parser, struct Statement* out)
 	if (value == NULL)
 		return false;
 
+	// conditional select: target = if_value if <cond> else else_value. The `if`
+	// must share the assignment's line, so a plain assignment followed by an
+	// `if` statement on the next line stays two statements.
+	if (op.type == TOKEN_EQUAL && !deref
+		&& check(parser, TOKEN_IF) && parser->current.line == name.line)
+	{
+		advance_parser(parser);
+
+		struct Expr* left;
+		struct Token comparison;
+		struct Expr* right;
+		if (!parse_condition(parser, &left, &comparison, &right))
+		{
+			free_expr(value);
+			return false;
+		}
+
+		struct Expr* else_value = NULL;
+		if (!consume(parser, TOKEN_ELSE, "expected 'else' in conditional select")
+			|| (else_value = parse_expression(parser)) == NULL)
+		{
+			free_expr(value);
+			free_expr(left);
+			free_expr(right);
+			return false;
+		}
+
+		out->kind = STATEMENT_SELECT;
+		out->select.target = name;
+		out->select.if_value = value;
+		out->select.left = left;
+		out->select.comparison = comparison;
+		out->select.right = right;
+		out->select.else_value = else_value;
+		return true;
+	}
+
 	out->kind = STATEMENT_ASSIGN;
 	out->assign.target_deref = deref;
 	out->assign.store_size = store_size;