摘要:

AbstractCreating back‐of‐the‐book indexes is a difficult task involving intelligent and clerical processes. Programs have generally not achieved the level of intelligence required to perform the intelligent process of selecting terms for the index. Semi‐automatic indexing programs perform the clerical process of preparing entries once the terms have been selected. The programs do not provide assistance in term determination and most require flooding the text with indexing commands. indx differs from other semi‐automatic indexing programs mainly because it does not require the insertion of indexing commands into the text to be indexed. The method by which indx assists in the creation of an index is introduced and compared with the characteristics of the other programs. This method includes the use of a program that aids the term determination process. The design, implementation, and application of indx are presented. Areas in which indx may be improved or enhanced are identified. An index of this paper created with indx is included as a

ISSN:0038-0644    

DOI:10.1002/spe.4380190104

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY

摘要:

AbstractObject‐oriented programming languages are noted for their ability to allow users quickly to construct large software systems. They achieve this ability by allowing the programmer to concentrate on what it is they want to do, ignoring details of how that functionality is achieved. Such characteristics should make the object‐oriented style of programming attractive to casual or novice computer users, indeed one of the best known object‐oriented programming languages, Smalltalk, was initially designed with just such novice users in mind.The Unix operating system is widely regarded as a good environment for doing software development. Nevertheless, its large number of often terse and cryptic commands make it difficult for novice or casual users to use. In this paper we argue that one solution is to create an object‐oriented command interpreter, or shell, between the user and the underlying system. This paper reports on the construction of one such prototype shell, and the lessons we have learned from the use of this

ISSN:0038-0644    

DOI:10.1002/spe.4380190105

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY

摘要:

AbstractSince a compiler phase depends on previous phases for input, it can be difficult to do timely independent unit testing of some phases. This can make integration more difficult and reduce overall quality. A test case generator has been used to circumvent this problem by providing an independent source of phase test inputs. Using a context‐free grammar augmented with contextsensitive constructs, a test case generator can generate intermediate language graphs in textual for

ISSN:0038-0644    

DOI:10.1002/spe.4380190106

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY

摘要:

AbstractIn recent years, several authors have presented algorithms that locate instances of a given string, or set of strings, within a text. Recently, authors have given less consideration to the complementary problem of processing a text to find out what strings appear in the text, without any preconceived notion of what strings might be present. A system called PATRICIA, which was developed two decades ago, is an implementation of a solution to this problem. The design of PATRICIA is very tightly bound to the assumptions that individual string elements are bits and that the user of the system can provide complete lists of starting and stopping places for strings. This paper presents an approach that drops these assumptions. Our method allows different definitions of indivisible string elements for different applications, and the only information the user provides for the determination of the beginning and ends of strings is a specification of a maximum length for output strings.This paper also describes a portable C implementation of the method, called PORTREP. The primary data structure of PORTREP is a trie represented as a ternary tree. PORTREP has a method for eliminating redundancy from the output, and it can function with a bounded number of nodes by employing a heuristic process that reuses seldom‐visited nodes. Theoretical analysis and empirical studies, reported here, give confidence in the efficiency of the algorithms. PORTREP has the ability to form the basis for a variety of text‐analysis applications, and this paper considers one such application, automatic document index

ISSN:0038-0644    

DOI:10.1002/spe.4380190107

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY

摘要:

AbstractAbstract machine modelling is a popular technique for developing portable compilers. A compiler can be quickly realized by translating the abstract machine operations to target machine operations. The problem with these compilers is that they trade execution efficiency for portability. Typically, the code emitted by these compilers runs two to three times slower than the code generated by compilers that employ sophisticated code generators. This paper describes a C compiler that uses abstract machine modelling to achieve portability. The emitted target machine code is improved by a simple, classical rule‐directed peephole optimizer. Our experiments with this compiler on four machines show that a small number of very general handwritten patterns (under 40) yields code that is comparable to the code from compilers that use more sophisticated code generators. As an added bonus, compilation time on some machines is reduced by 10 to 20 per cen

ISSN:0038-0644    

DOI:10.1002/spe.4380190108

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY

ISSN:0038-0644    

DOI:10.1002/spe.4380190103

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY