add readTriple in the Haskell binding

1 files changed, 35 insertions, 2 deletions

diff --git a/src/runtime/c/pgf/expr.c b/src/runtime/c/pgf/expr.c
index af849817c..3482e0b11 100644
--- a/src/runtime/c/pgf/expr.c
+++ b/src/runtime/c/pgf/expr.c
@@ -607,7 +607,8 @@ pgf_expr_parser_expr(PgfExprParser* parser)
 		       parser->token_tag != PGF_TOKEN_RPAR &&
 		       parser->token_tag != PGF_TOKEN_RCURLY &&
 		       parser->token_tag != PGF_TOKEN_RTRIANGLE &&
-		       parser->token_tag != PGF_TOKEN_COLON) {
+		       parser->token_tag != PGF_TOKEN_COLON &&
+		       parser->token_tag != PGF_TOKEN_COMMA) {
 			PgfExpr arg = pgf_expr_parser_arg(parser);
 			if (gu_variant_is_null(arg))
 				return gu_null_variant;
@@ -798,7 +799,7 @@ PgfExpr
 pgf_read_expr(GuIn* in, GuPool* pool, GuExn* err)
 {
 	GuPool* tmp_pool = gu_new_pool();
-	PgfExprParser* parser = 
+	PgfExprParser* parser =
 		pgf_new_parser(in, pool, tmp_pool, err);
 	PgfExpr expr = pgf_expr_parser_expr(parser);
 	if (parser->token_tag != PGF_TOKEN_EOF)
@@ -807,6 +808,38 @@ pgf_read_expr(GuIn* in, GuPool* pool, GuExn* err)
 	return expr;
 }
 
+int
+pgf_read_expr_tuple(GuIn* in,
+                    int n_exprs, PgfExpr exprs[],
+                    GuPool* pool, GuExn* err)
+{
+	GuPool* tmp_pool = gu_new_pool();
+	PgfExprParser* parser =
+		pgf_new_parser(in, pool, tmp_pool, err);
+	if (parser->token_tag != PGF_TOKEN_LTRIANGLE)
+		return 0;
+	pgf_expr_parser_token(parser);
+	for (size_t i = 0; i < n_exprs; i++) {
+		if (i > 0) {
+			if (parser->token_tag != PGF_TOKEN_COMMA)
+				return 0;
+			pgf_expr_parser_token(parser);
+		}
+
+		exprs[i] = pgf_expr_parser_expr(parser);
+		if (gu_variant_is_null(exprs[i]))
+			return 0;
+	}
+	if (parser->token_tag != PGF_TOKEN_RTRIANGLE)
+		return 0;
+	pgf_expr_parser_token(parser);
+	if (parser->token_tag != PGF_TOKEN_EOF)
+		return 0;
+	gu_pool_free(tmp_pool);
+
+	return 1;
+}
+
 PgfType*
 pgf_read_type(GuIn* in, GuPool* pool, GuExn* err)
 {