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The authors provide a brief history of the firm now called East View Information Services. From its beginning in 1989 as a sole-proprietorship company, it has grown from microfilming the back file of a single Soviet journal to being a subscription agent, book vendor, database aggregator, provider of maps and other geospatial information, and more—from Slavic countries, East Asia, the Middle East, and elsewhere.

Many language implementations, like C++ and Java, check the types of values and operations to be sure each operation is supported for the types of its operands. An important feature of Standard ML is the type inference system which is somewhat like the type checkers of C++ and Java, but a bit more powerful. A type checker checks the types written by the programmer to be sure each type declaration is consistent with the operations being performed, values being passed to functions, and the values being returned. Compilers for Java and C++ even infer the types of some expressions when polymorphic operators are used. For instance, the addition operator has multiple result types depending on the types of its operands.

The ML in the name Standard ML stands for meta-language. SML was designed as a language for describing languages when it was used as part of the Logic for Computable Functions (LCF) system [9]. Two tools were designed to work with Standard ML for language implementation, ML-lex and ML-yacc. The pattern matching, ease of defining recursive datatypes, the functional nature of the language along with these two tools make Standard ML an excellent language choice for implementing interpreters and compilers.

In November, 2004 the National Geospatial-Intelligence Agency (NGA) announced its intention to withdraw essentially all of its aeronautical chart and related digital data publications from public distribution. Citing multiple concerns (potential use by terrorists, potential threats to the integrity of its own data, and commercial/copyright issues), NGA's proposed withdrawal would have removed huge volumes of traditionally open data from public access and established ominous precedents in the post-9/11 environment. Map libraries of all kinds would have been affected correspondingly. The paper seeks to explore each stated rationale by NGA, and also seeks to explain all NGA product series, including some rather arcane digital products, that were at stake for withdrawal.

This paper provides a description of a framework for programming language implementation that is accessible to students in a one semester course focused on programming languages. Rather than concentrating solely on language features, this paper describes a framework where imperative, functional, and logic programming languages are all used to develop a compiler for a non-trivial subset of a functional programming language. Provided by the framework are a virtual machine, a disassember of Python programs, a partial implementation of a Standard ML compiler with suggested tests, and a partial implementation of a type inference system implemented using Prolog, again with suggested tests. Classroom experience gained while using this framework is also shared. A suggested fourteen week sequence is provided. Real reactions from students and reflections on coverage of the ACM 2013 Curricula guildelines conclude the paper.

When using formal methods to generate compilers it is desirable for all levels of the compiler to be formally specified. Typically, register allocation has been thought to be equivalent to graph coloring. Since graph coloring is NP-Complete most algorithms for register allocation have been ad-hoc. This paper presents a framework for register allocation that has been formally verified using an inductive theorem prover.

Access to global geospatial data, and the way these data are being used, has changed dramatically in the past decade. This is true for a variety of reasons, many of them not readily apparent. This article will explore some of the essential changes in this sphere since the early 1990s, as seen from the perspective of a commercial distributor and service bureau involved with international maps and related data.

This documentation was generated from the Python documentation available by typing from turtle import * help (TurtleScreen) in the Python shell.

This documentation was generated from the Python documentation available by typing from turtle import * help (Turtle) in the Python shell.

This first chapter introduces Python to readers that have never programmed in Python before. It also provides instructions for installing Python on your computer. The Wing Integrated Development Environment (IDE) is recommended for students learning to program. Wing IDE 101 is the free version of the IDE for educational use. The chapter goes on to introduce classes, objects, and object-oriented programming by developing a drawing application using the Tkinter graphical user interface library. An understanding of object-oriented programming concepts presented in this chapter is necessary before reading the rest of the text. The PyList datatype presented in this chapter is also used in subsequent chapters including Chap. 2. Even if the reader has worked through an introductory text or has a basic understanding of Python, there are concepts from this first chapter that are used throughout the text.

This documentation was generated from the Python documentation available by typing help(list) in the Python shell.

This documentation was generated from the Python documentation available by typing help(dict) in the Python shell.

This documentation was generated from the Python documentation available by typing help(int) in the Python shell.

This documentation was generated from the Python documentation available by typing help(float) in the Python shell.

This documentation was generated from the Python documentation available by typing help(str) in the Python shell.

Introduction Syntax Assembly Language C++ Standard ML Compiling Standard ML Prolog Type Inference The CoCo Virtual Machine Specification The Standard ML Basis Library

JCoCo is a virtual machine which includes a built-in assembler. JCoCo executes assembly language programs by first processing the assembly language program and then executing it. The processing of the assembly language program is called assembling.

Chapter six introduces event-driven programming. In an event-driven program, the program goes to an event queue to find the next event and then calls some code to process that event. Graphical User Interface (GUI) programs operate like this. Chapter six introduces event-driven programming using Tkinter, a graphical user interface library for Python programmers.