Basic Pascal Tutorial/Chapter 3/WHILE..DO: what changed

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Title: Basic Pascal Tutorial/Chapter 3/WHILE..DO

New		Line
1	+	## While ... DO loops
2	+
3	+	3Db - WHILE..DO (author: Tao Yue, state: unchanged)
4	+
5	+	The pretest loop has the following format:
6	+
7	+	``` pascal
8	+	while BooleanExpression do
9	+	statement;
10	+	```
11	+
12	+	The loop continues to execute until the Boolean expression becomes `FALSE`. In the body of the loop, you must somehow affect the Boolean expression by changing one of the variables used in it. Otherwise, an infinite loop will result:
13	+
14	+	``` pascal
15	+	a := 5;
16	+	while a < 6 do
17	+	writeln (a);
18	+	```
19	+
20	+	Remedy this situation by changing the variable's value:
21	+
22	+	``` pascal
23	+	a := 5;
24	+	while a < 6 do
25	+	begin
26	+	writeln (a);
27	+	a := a + 1
28	+	end;
29	+	```
30	+
31	+	The `WHILE ... DO` loop is called a pretest loop because the condition is tested before the body of the loop executes. So if the condition starts out as `FALSE`, the body of the `while` loop never executes.
32	+
33	+	## See also
34	+
35	+	- [[Basic Pascal Tutorial/Chapter 3/FOR..DO\|FOR ...DO loops]]
36	+	- [[Until\|Repeat... Until loops]]
37	+	- [[for-in loop\|For... in loops]]
38	+
39	+	---
40	+	From the Free Pascal wiki, page "Basic Pascal Tutorial/Chapter 3/WHILE..DO", as it stood on 2022-08-20 after a change by Kai Burghardt, out of the wiki's dump of 2024-05-26. Copyright stays with the author who wrote it, according to the old wiki's [[Licensing]] page. If you have concerns about this material, [message the admin](/wiki-contact).