Structured English is the use of the English language with the syntax of structured programming to communicate the design of a computer program to non-technical users by breaking it down into logical steps using straightforward English words. Structured English aims to get the benefits of both the programming logic and natural language: program logic helps to attain precision, whilst natural language helps with the familiarity of the spoken word.
It is the basis of some programming languages such as SQL (Structured Query Language) "for use by people who have need for interaction with a large database but who are not trained programmers".
Structured English is a limited form "pseudocode" and consists of the following elements:
- Operation statements written as English phrases executed from the top down
- Conditional blocks indicated by keywords such as IF, THEN, and ELSE
- Repetition blocks indicated by keywords such as DO, WHILE, and UNTIL
The following guidelines are used when writing Structured English:
- All logic should be expressed in operational, conditional, and repetition blocks
- Statements should be clear and unambiguous
- Logical blocks should be indented to show relationship and hierarchy
- Use one line per logical element, or indent the continuation line
- Keywords should be capitalized
- Group blocks of statements together, with a capitalized name that describes their function and end with an EXIT.
- Underline words or phrases defined in a data dictionary
- Mark comment lines with an asterisk
Example of Structured English
A bank will grant loan under the following conditions
- If a customer has an account with the bank and had no loan outstanding, loan will be granted.
- If a customer has an account with the bank but some amount is outstanding from previous loans then loan will be granted if special approval is given.
- Reject all loan applications in all other cases.
APPROVE LOAN IF customer has a Bank Account THEN IF Customer has no dues from previous account THEN Allow loan facility ELSE IF Management Approval is obtained THEN Allow loan facility ELSE Reject ENDIF ENDIF ELSE Reject ENDIF EXIT
Though useful for planning programs, modules and routines, or describing algorithms it is less useful when numerous decisions need to be made.
Other Specification Tools
- Natural language programming
- Self-documenting code
- Structured programming
- Decision Tree
- Decision tables
- ""What is Structured English", Wisegeek.com, retrieved 23 April 2014
- "Implementation of a Structured English Query Language" M.M. Astrahan and D.D. Chamberlain, IBM Research Division, San Jose, ACM, May 1975 (retrieved from Cleveland State University website, April 2014)
- "Guidelines for Structured English in Documenting Specifications", Craig Borysowich, IT Toolbox, 29 April 2007
- "Ch. 60 Structured English, Strengths and Weaknesses", The Information Systems: Analysis and Design, Meyzin Leonid, Holon Institute of Technology, retrieved 23 April 2014