Micro Focus Enterprise Developer 2.3 for Visual Studio 2015 > General Reference > Open PL/I Language Reference Manual > Open PL/I Macro Preprocessor > Preprocessor Statements > %DO

%DO

Purpose

Begins a sequence of preprocessor statements to be executed in a group.

Syntax

%[labe1:]... DO[index = start[TO finish[BY increment]] | 
                                  [BY increment [TO finish]]];

Parameters

Where index is a preprocessor variable; start, finish, and increment are preprocessor expressions.

Description

The %DO statement and its corresponding %END statement delimit a preprocessor DO group and can also specify repetitive execution of the DO group.

Preprocessor DO groups can be nested. Both preprocessor statements and text other than preprocessor statements can appear within a preprocessor DO group. However, only the preprocessor statements are executed. Nonpreprocessor statements are scanned but only for possible replacement activity. Non-iterative preprocessor DO groups are useful as THEN or ELSE clauses of %IF statements.

If increment is ≤ 0 or start > finish, the body of the loop is not executed.

Example

%DECLARE IX FIXED; 
%DO IX = 1 TO 4; 
A(IX) = IX;
%END

The text generated by this example would be as follows:

A(1) = 1;
A(2) = 2;
A(3) = 3;
A(4) = 4;