冶金熱力學數據庫應用系統怎樣檢查用戶命令

Checking of User's Commands in METHEDAS

摘要: 本文介紹了METHEDAS怎樣檢查用戶命令。根據用戶命令的語法結構,對其進行三方面檢查:
(1)命令關鍵字及格式。
(2)參數關鍵字及格式,參數的數據類型。
(3)命令與參數的搭配關系。
上述任務由用戶命令解釋程序的換碼模塊和語法檢查模塊完成。
METHEDAS的用戶命令解釋程序用FORTRAN-Ⅳ實現。它簡單、實用、便于移植。在編制程序過程中較好地模擬了FORTRAN77的字符處理功能。

Abstract: Checking of user's commands in METHEDAS is the main subject in this paper.On basis of the syntactic structures of user's commands, the checking on following items:
1. command keywords and formats
2. parameter keywords, formats and their data types
3. rules of jointing commands with parameters
is completed by means of a code conversion module and a syntax parsing module, which compose an interpreter.
This interpreter, constructed within the FORTRAN-4 framework, is very successful in its simplicity, usefulness, and ability of simulating the string processing function, possessed by FORTRAN-77.