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9.110 if

Synopsis

 
if Boolean expression then
  statement
or with an alternative statement:
 
if Boolean expression then
  statement1
else
  statement2

Description

The `if ... then' statement executes statement1 depending on `Boolean expression' being true. If `else' is specified, it continues executing statement2 instead.

Conforming to

`if' is defined in ISO-7185 Pascal and supported by all Pascal variants.

Example

 
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.

See also

section 8.1.7.3 if Statement, section 9.68 else, section 9.274 then



This document was generated by Frank Heckenbach on May, 10 2002 using texi2html