Simple DO:

  
<group>                 ::= <group head> <ending>

<group head>            ::= DO ;
                          | <group head> <statement>

<ending>                ::= END
                          | END <identifier>
                          | <label definition> <ending> 
 









This form of the DO statement allows execution of a group of statements one time. The purpose is to group statements so that they can be substituted where a <basic statement> is required, for example, in the <true part> of an IF statement.

Example: 


if a=5 then
  do;  
    output = 'The value is 5,';
    output = ' and that''s the truth.';
  end;