Augmenting Source Code Lines with Sample Variable Values

Source code is inherently abstract, which makes it difficult to understand. Activities such as debugging can reveal concrete runtime details, including the values of variables. However, they require that a developer explicitly requests these data for a specific execution moment. We present a simple approach, RuntimeSamp, which collects sample variable values during normal executions of a program by a programmer. These values are then displayed in an ambient way at the end of each line in the source code editor. We discuss questions which should be answered for this approach to be usable in practice, such as how to efficiently record the values and when to display them. We provide partial answers to these questions and suggest future research directions

From Eager PFL to Lazy Haskell

The state of a system is expressed using PFL, a process functional language, in an easily understandable manner. The paper presents PFL environment variable -- our basic concept for the state manipulation in the process functional language. Then we introduce the style in which stateful systems are described using monads and state transformers in pure lazy functional language Haskell. Finally, we describe our approach to lazy state manipulation in PFL and correspondence between state manipulation in PFL and the one in a pure lazy functional language Haskell. The proposed translation from eager PFL to a lazy Haskell provides an opportunity to exploit laziness for process functional programs and furthermore for imperative programs. The approach described in this paper was used in implemented PFL to Haskell code generator

Separating Concerns in Programming: Data, Control and Actions

A multi-paradigm language provides an opportunity to a user for exploiting more programming methodologies. It simplifies the language syntax, and extends the application areas by the extended semantics. That is why multi-paradigm languages can align a problem in wider application areas and more flexibly than that based on a single paradigm. In this paper, we present the idea of separating three essential concerns of programming currently being implemented in PFL -- a process functional language. We separate data, control, and actions by the definition of a purely control structure. Then, by the structured application of a structure of actions to a purely control structure, we will express the computation of activated actions in a structured way, considering explicitly defined synchronization in computation