Difference between revisions of "If and Then"
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− | <code>condition</code> is a [[boolean]] expression that evaluates to [[True|true]] xor [[False|false]]. | + | <code>condition</code> is a [[Boolean|boolean]] expression that evaluates to [[True|true]] xor [[False|false]]. |
<code>true_statement</code> is executed if <code>condition</code> evaluates to <code>true</code>. | <code>true_statement</code> is executed if <code>condition</code> evaluates to <code>true</code>. | ||
<code>false_statement</code> is executed if <code>condition</code> evaluates to <code>false</code>. | <code>false_statement</code> is executed if <code>condition</code> evaluates to <code>false</code>. | ||
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− | === | + | === Multiple statements in <code>if then</code> branch === |
− | If you need two or more statements for <code>true_statement</code> or <code>false_statement<code>, enclose them within a <code>[[Begin|begin]] … [[End|end]]</code> [[Block]] (compound statement). | + | If you need two or more statements for <code>true_statement</code> or <code>false_statement</code>, enclose them within a <code>[[Begin|begin]] … [[End|end]]</code> [[Block]] (compound statement). |
<syntaxhighlight> | <syntaxhighlight> | ||
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− | == | + | == See also == |
− | * | + | * Official documentation: [https://www.freepascal.org/docs-html/ref/refsu57.html Reference guide: § “The <code>If..then..else</code> statement”] |
+ | * [[IF]], Tao Yue, Object Pascal Introduction | ||
{{Keywords}} | {{Keywords}} | ||
[[Category:Pascal]] | [[Category:Pascal]] | ||
[[Category:Control Structures]] | [[Category:Control Structures]] |
Revision as of 10:07, 24 January 2018
│
English (en) │
The if
keyword precedes a condition, must be followed by then
and a statement. The statement may optionally be followed by else
and another statement.
If then
if condition
then true_statement
else false_statement;
condition
is a boolean expression that evaluates to true xor false.
true_statement
is executed if condition
evaluates to true
.
false_statement
is executed if condition
evaluates to false
.
A compile-time error occurs if the type of condition
does not evaluate to a boolean
value.
Multiple statements in if then
branch
If you need two or more statements for true_statement
or false_statement
, enclose them within a begin … end
Block (compound statement).
if boolean_condition then
begin
statement_zero;
statement_one;
statement_two;
end;
See also
- Official documentation: Reference guide: § “The
If..then..else
statement” - IF, Tao Yue, Object Pascal Introduction
Keywords: begin — do — else — end — for — if — repeat — then — until — while