Difference between revisions of "Shr"
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| + | {{Shr}} | ||
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| + | Back to [[Reserved words]]. | ||
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== Overview == | == Overview == | ||
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| − | + | The reserved word '''Sh'''ift '''r'''ight (shr) performs a logical right bit-shift operation (opposite than [[Shl|shl]]). | |
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| − | '''Sh'''ift '''r'''ight (shr) performs a logical right bit-shift operation (opposite than [[Shl|shl]]). | ||
== Shr with signed types == | == 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. | 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. | ||
| − | <syntaxhighlight> | + | <syntaxhighlight lang=pascal> |
program ShrTest; | program ShrTest; | ||
begin | begin | ||
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== Is a bit set == | == Is a bit set == | ||
| − | <syntaxhighlight> | + | <syntaxhighlight lang=pascal> |
function isBitSet(AValue, ABitNumber:integer):boolean; | function isBitSet(AValue, ABitNumber:integer):boolean; | ||
begin | begin | ||
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</syntaxhighlight> | </syntaxhighlight> | ||
| − | + | {{Logical operators}} | |
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* [[Const]] | * [[Const]] | ||
* [[Function]] | * [[Function]] | ||
* [[Integer]] | * [[Integer]] | ||
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Revision as of 23:38, 16 October 2020
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Back to Reserved words.
Overview
The reserved word Shift right (shr) performs a logical right bit-shift operation (opposite than shl).
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;
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