Exploring Possibilities of Language for Describing the Problem

• Main Authors: Elizaveta Dorenskaya, Anna Kulikovskaya, Yuri Semenov
• Format: Article
• Language: Russian
• Published: The Fund for Promotion of Internet media, IT education, human development «League Internet Media» 2020-11-01
• Series: Современные информационные технологии и IT-образование
• Subjects: problem description language; pdl; non-algorithmic language; problem description; translator; analysis; synthesis; perl; primitive
• Online Access: http://sitito.cs.msu.ru/index.php/SITITO/article/view/697

The problem description language (PDL) has been developed. The main architectural features of the PDL language are considered. The advantages of using PDL are discussed. The rules for creating descriptions in PDL are described. A universal software configurator for the Web server security software package is considered. Here is an example of testing PDL using a translator that converts the task description to the executable Perl code. The structure of the PDL task description translator in Perl (analysis phase and synthesis phase) is given. The features of this translator at the synthesis stage [13-15, 24, 26, 27] are described. There are 3 modes of operation at the synthesis phase: 1. If the task description does not specify any of the action operators (a special class of operators in the PDL). 2. If the description contains at least one action operator and you need to search the algorithm in the database. 3. If the required module is not found in the algorithm bank under the same conditions as in point 2. In the first case, primitives are used. The second one searches for modules in the algorithm bank. In the 3rd case, the required module must be partially written by the programmer himself. The procedure for generating a web server security software package in Perl using the PDL task description is considered. Examples are given and the reasons for reducing the number of program errors when using the PDL translator in Perl are described.