Spoofax at Oracle: Domain-Specific Language Engineering for Large-Scale Graph Analytics

For the last decade, teams at Oracle relied on the Spoofax language workbench to develop a family of domain-specific languages for graph analytics in research projects and in product development. In this paper, we analyze the requirements for integrating language processors into large-scale graph analytics toolkits and for the development of these language processors as part of a larger product development process. We discuss how Spoofax helps to meet these requirements and point out the need for future improvements

Random Term Generation for Compiler Testing in Spoofax

Testing is the most commonly used technique for raising confidence in the correctness of a piece of software, but constructing an effective test suite is expensive and prone to error. Property-based testing partly automates this process by testing whether a property holds for all randomly generated inputs, but its effectiveness depends upon the ability to automatically generate random test inputs. When using property-based testing to test a compiler backend, the problem becomes that of generating random programs that pass the parsing and analysis phase. We present SPG (SPoofax Generator), a language-parametric generator of random well-formed terms. We describe three experiments in which we evaluate the effectiveness of SPG at discovering different kinds of compiler bugs. Furthermore, we analyze why the generator fails to detect certain compiler bugs and provide several ideas for future work. The results show that random testing can be a cost-effective technique to find bugs in small programming languages (such as DSLs), but its application to practical programming languages requires further research

Reliability and Reproducibility of the OTA/AO Classification for Humeral Shaft Fractures

Objectives: This study aimed to determine interobserver reliability and intraobserver reproducibility of the OTA/AO classification for humeral shaft fractures, and to evaluate differences between fracture types, fracture groups, and surgical specializations. Methods: Thirty observers (25 orthopaedic trauma surgeons and 5 general orthopaedic surgeons) independently classified 90 humeral shaft fractures according to the OTA/AO classification. Patients of 16 years and older were included. Periprosthetic, recurrent, and pathological fractures were excluded. Radiographs were provided in random order, and observers were blinded to clinical information. To determine intraobserver agreement, radiographs were reviewed again after 2 months in a different random order. Agreement was assessed using kappa statistics. Results: Interobserver agreement for the 3 fracture types was moderate (κ = 0.60; 0.59-0.61). It was substantial for type A (κ = 0.77; 0.70-0.84) and moderate for type B (κ = 0.52; 0.46-0.58) and type C fractures (κ = 0.46; 0.42-0.50). Interobserver agreement for the 9 fracture groups was moderate (κ = 0.48; 95% CI, 0.48-0.48). Orthopaedic trauma surgeons had better overall agreement for fracture types, and general orthopaedic surgeons had better overall agreement for fracture groups. Observers classified 64% of fractures identically in both rounds. Intraobserver agreement was substantial for the 3 types (κ = 0.80; 0.77-0.81) and 9 groups (κ = 0.80; 0.77-0.82). Intraobserver agreement showed no differences between surgical disciplines. Conclusions: The OTA/AO classification for humeral shaft fractures has a moderate interobserver and substantial intraobserver agreement for fracture types and groups

HUMeral shaft fractures: measuring recovery after operative versus non-operative treatment (HUMMER): a multicenter comparative observational study

Fractures of the humeral shaft are associated with a profound temporary (and in the elderly sometimes even permanent) impairment of independence and quality of life. These fractures can be treated operatively or non-operatively, but the optimal tailored treatment is an unresolved problem. As no high-quality comparative randomized or observational studies are available, a recent Cochrane review concluded there is no evidence of sufficient scientific quality available to inform the decision to operate or not. Since randomized controlled trials for this injury have shown feasibility issues, this study is designed to provide the best achievable evidence to answer this unresolved problem. The primary aim of this study is to evaluate functional recovery after operative versus non-operative treatment in adult patients who sustained a humeral shaft fracture. Secondary aims include the effect of treatment on pain, complications, generic health-related quality of life, time to resumption of activities of daily living and work, and cost-effectiveness. The main hypothesis is that operative treatment will result in faster recovery. The design of the study will be a multicenter prospective observational study of 400 patients who have sustained a humeral shaft fracture, AO type 12A or 12B. Treatment decision (i.e., operative or non-operative) will be left to the discretion of the treating surgeon. Critical elements of treatment will be registered and outcome will be monitored at regular intervals over the subsequent 12 months. The primary outcome measure is the Disabilities of the Arm, Shoulder, and Hand score. Secondary outcome measures are the Constant score, pain level at both sides, range of motion of the elbow and shoulder joint at both sides, radiographic healing, rate of complications and (secondary) interventions, health-related quality of life (Short-Form 36 and EuroQol-5D), time to resumption of ADL/work, and cost-effectiveness. Data will be analyzed using univariate and multivariable analyses (including mixed effects regression analysis). The cost-effectiveness analysis will be performed from a societal perspective. Successful completion of this trial will provide evidence on the effectiveness of operative versus non-operative treatment of patients with a humeral shaft fracture. The trial is registered at the Netherlands Trial Register (NTR3617