NYI: Visual Programming Languages (Scaling Up)

直观编程是非常吸引人的，因为它允许程序员通过简单地描绘数据、指向数据或演示数据来表达数据之间的关系或转换——而不是将它们转换成命令、指针和抽象符号的序列。这种消除了传统上编程计算机所需要的许多概念，加上连续的视觉反馈，使编程变得更容易、更可靠。然而，有一个问题导致可视化编程的潜力在很大程度上仍未得到开发。迄今为止，大多数可视化编程语言（vpl）都不容易扩展到小型演示程序之外，以便在不重新引入它们试图删除的概念的情况下充分处理实际编程。这个问题被称为放大问题。本研究的目的是提高vpl的可扩展性。重点在三个方面：(1)开发增强表达能力和代码重用的方法，同时保持简单和具体的品质；(2)开发适合vpl的隐式多态类型的具体方法；(3)扩大vpl的适用性。这三个方向的研究成果在研究系统Forms/3中进行了原型化，这是一种懒惰的声明性视觉语言。

Visual programming is intuitively very appealing, because it allows the programmer to express relationships among, or transformations to, data simply by sketching them, pointing at them, or demonstrating them -- not by translating them into sequences of commands, pointers, and abstract symbols. This removal of many of the concepts traditionally required to program computers, combined with continuous visual feedback, offers the promise of making programming easier and more reliable. Yet, there is a problem that has caused the potential of visual programming to remain largely untapped. Most visual programming languages (VPLs) to date are not easily extended beyond small demonstration programs to adequately handle realistic programming without re-introducing the very concepts they have tried to remove. This problem is called the scaling-up problem. The objective of this research is to improve the scalability of VPLs. The focus is in three directions: (1) developing ways to increase expressive power and code reuse that also maintain the qualities of simplicity and concreteness; (2) developing a concrete approach to implicit polymorphic types suitable for VPLs; and (3) extending the applicability of VPLs. Research results from investigating these three directions are prototyped in the research system Forms/3, a lazy declarative visual language.