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if Boolean expression then statement |
if Boolean expression then statement1 else statement2 |
The `if ... then' statement executes statement1 depending on `Boolean expression' being true. If `else' is specified, it continues executing statement2 instead.
`if' is defined in ISO-7185 Pascal and supported by all Pascal variants.
program IfDemo;
var
Foo, Bar: Boolean;
begin
Foo := True;
Bar := False;
if ((1 = 1) or (2 = 3)) and (Foo = not Bar) then
begin
{ This is executed if either Foo is true but not Bar or vice versa }
WriteLn ('Either Foo or Bar is true.');
if Bar then
WriteLn ('You will see this text if Bar is true.')
end
else { This whole `else' branch is not executed }
if 1 = 1 then
if True = False then
WriteLn ('This text is never written on screen.')
else { Note: This ``else'' belongs to ``if True = False'' }
WriteLn ('This text is never written on screen as well.')
else { Note: This ``else'' belongs to ``if 1 = 1'' }
WriteLn ('Nor is this.')
end.
|
section 8.1.7.3 if Statement, section 9.68 else, section 9.274 then