Function _Validate_apply_all_operator

src/ast/ast_validations.c:551–580

validate an apply-all operator

// validate an apply-all operator
static VISITOR_STRATEGY _Validate_apply_all_operator
(
	const cypher_astnode_t *n,  // ast-node
	bool start,                 // first traversal
	ast_visitor *visitor        // visitor
) {
	validations_ctx *vctx = AST_Visitor_GetContext(visitor);
	if(!start) {
		return VISITOR_CONTINUE;
	}

	// Working with a function call that has * as its argument.
	const cypher_astnode_t *func = cypher_ast_apply_all_operator_get_func_name(n);
	const char *func_name = cypher_ast_function_name_get_value(func);

	// Verify that this is a COUNT call.
	if(strcasecmp(func_name, "COUNT")) {
		ErrorCtx_SetError("COUNT is the only function which can accept * as an argument");
		return VISITOR_BREAK;
	}

	// Verify that DISTINCT is not specified.
	if(cypher_ast_apply_all_operator_get_distinct(n)) {
		// TODO consider opening a parser error, this construction is invalid in Neo's parser.
		ErrorCtx_SetError("Cannot specify both DISTINCT and * in COUNT(DISTINCT *)");
		return VISITOR_BREAK;
	}

	return VISITOR_RECURSE;
}

// validate an apply operator
static VISITOR_STRATEGY _Validate_apply_operator