Difference between revisions of "REPEAT..UNTIL"

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m (Text replace - "delphi>" to "syntaxhighlight>")
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The posttest loop has the following format:
 
The posttest loop has the following format:
<delphi>
+
<syntaxhighlight>
 
repeat
 
repeat
 
   statement1;
 
   statement1;
 
   statement2
 
   statement2
 
until BooleanExpression;
 
until BooleanExpression;
</delphi>
+
</syntaxhighlight>
  
 
In a <tt>repeat</tt> loop, compound statements are built-in -- you don't need to use begin-end. Also, the loop continues until the Boolean expression is <tt>TRUE</tt>, whereas the <tt>while</tt> loop continues until the Boolean expression is <tt>FALSE</tt>.
 
In a <tt>repeat</tt> loop, compound statements are built-in -- you don't need to use begin-end. Also, the loop continues until the Boolean expression is <tt>TRUE</tt>, whereas the <tt>while</tt> loop continues until the Boolean expression is <tt>FALSE</tt>.

Revision as of 15:54, 24 March 2012

REPEAT..UNTIL (author: Tao Yue, state: unchanged)

The posttest loop has the following format:

repeat
  statement1;
  statement2
until BooleanExpression;

In a repeat loop, compound statements are built-in -- you don't need to use begin-end. Also, the loop continues until the Boolean expression is TRUE, whereas the while loop continues until the Boolean expression is FALSE.

This loop is called a posttest loop because the condition is tested after the body of the loop executes. The REPEAT loop is useful when you want the loop to execute at least once, no matter what the starting value of the Boolean expression is.

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