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Revision 1 of 2, by Trev on 2-21-2020. The page as it is now.

Not/fr


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Opération booléenne

Not produit une valeur true si la valeur de l'opérande est false et inversement.

Table de vérité

A Not A
  false     true
  true     false  

Opération bit à bit

not bit à bit inverse les bits (1 devient 0, 0 devient 1).

Complément à 1

pascal
 function OnesComplement ( const aValue : byte ): byte;
 begin
   result := Not AValue;
 end;

Si vous appelez OnesComplement(%10000000), vous obtenez alors %01111111 (%10000000 = 128 et %01111111 = 127). Si vous appelez OnesComplement(%00000111), vous obtenez 248 (248 = %11111000).

pascal
 function OnesComplement2 ( const aValue : shortint ): shortint;
 begin
   result := Not AValue;
 end;

If you call OnesComplement2(%00000010) then get %11111101 (%00000010 = 2 and %11111101 = -3 when type is shortint). If you call OnesComplement2(7) then get -8 (-8 = %11111000 when type is shortint and 7 = %00000111 ).

See also


From the Free Pascal wiki, page "Not/fr", as it stood on 2020-02-21 after a change by Trev, 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.