Before we delve into the nitty-gritty of the “EXIT” in COBOL, it’s key to understand the relevance of the term in the world of programming. Exit is as simple as it appears; it signifies the end of a program or a loop, making it an indispensable element in the procedural programming paradigm. This functionality allows for enhanced control over the execution of the program and is widely used across programming languages, including COBOL. The Control flow in COBOL tends to allow for complex nested structures, thus appropriately incorporating and understanding the use of the EXIT statement becomes even more pertinent.
Integrating an EXIT statement in a COBOL program:
The solution to the effective use of EXIT revolves around understanding how this command changes the program flow. The EXIT statement signifies the end of a portion of the code but does not necessarily halt the execution of the program entirely. They represent an inert statement in the program, a sort of placeholder or dummy statement that does not perform any function or processing.
How To Use EXIT In COBOL
Understanding the syntax and structure of the EXIT statement can help one navigate its application effectively. Here’s how you can integrate the EXIT statement in the COBOL program following a step-by-step approach.
Procedure Division.
Some-Procedure Section.
Begin.
Display “Welcome to the COBOL tutorial!”.
Exit.
End.
The program starts with the Procedure Division, housing a section named Some-Procedure Section. This section then calls upon a paragraph named Begin. The Begin paragraph displays a message and then calls the EXIT statement, leading to the end of the paragraph routine.
Note: EXIT in COBOL doesn’t involve any sort of condition-check, error-check, or debugging of code.
Working With Nested Structures
Working with nested structures in COBOL is a common sight. However, managing the flow of control can be a challenge without the use of the EXIT statement.
Procedure Division.
First-Procedure Section.
Begin1.
Display “You’ve entered the first procedure”.
Second-Procedure Section.
Begin2.
Display “You’ve entered the second procedure”.
Exit.
End2.
Exit.
End1.
In this code, there are two sections within the Procedure Division, namely First-Procedure and Second-Procedure. Both contain paragraphs marked by Begin1 and Begin2 respectively. The EXIT statement is used to denote the end of these paragraph routines.
Key points to remember:
- EXIT gives us the flexibility to control the flow of execution in the program, especially with nested structures.
- While EXIT does not perform any specific functionality, it does play a crucial role in the structural organization of the COBOL program.
- Understanding the difference in the application of EXIT between COBOL and other programming languages can lead to more effective cross-language programming.
Differences In EXIT Usage Across Languages
Though the concept remains the same, the application of EXIT varies among programming languages. This variance is evident in the tolerance of syntax, semantics, and the role of EXIT in controlling the loop structures.
