Shr

Back to Reserved words.

Overview

The reserved word Shift right (shr) performs a logical right bit-shift operation (opposite than shl).

Example:

Command is: 00000100 shr 2 (shift right 2 bits)
 
Action is:  00000100 -> 00 (00 gets added to the left of the value; right 00 "disappears")
 
Result is:  00000001

Shr with signed types

Note: unlike the >> operator in the C language, the shr operator is a logical (not arithmetic) bit shift, even if the left operand is a signed integer. An implicit typecast and extension to a larger unsigned type may be performed before the shift operation. Check what the following program actually prints.

program ShrTest;
begin
  WriteLn(ShortInt(-3) shr 1);
end.

Is a bit set

function isBitSet(AValue, ABitNumber:integer):boolean;
begin
   result:=odd(AValue shr ABitNumber);
end;

• Const
• Function
• Integer

From the Free Pascal wiki, page "Shr", as it stood on 2021-09-01 after a change by Mozi, 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.