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Back to Reserved words.


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


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;
  WriteLn(ShortInt(-3) shr 1);

Is a bit set

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

navigation bar: Pascal logical operators

and • or • not • xor
shl • shr
and_then (N/A)• or_else (N/A)

see also

{$boolEval} • Reference: § “boolean operators” • Reference: § “logical operators”