Boolean Types 
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Here is a list of variations about Delphi's standard 1-byte "boolean" type:

type
  TPBoolean   = ^boolean;

  TSBoolean   = set of boolean;
  TPSBoolean  = ^TSBoolean;

  TABoolean   = array [0..maxInt-1] of boolean;
  TPABoolean  = ^TABoolean;

  TDABoolean  = array of boolean;
  TPDABoolean = ^TDABoolean;

Then we have an extended (but also 1-byte) boolean type, which knows 3 different states. BTW, you can directly typecast a "boolean" value into a "TExtBool" value. A "false" will automatically be typecasted to a "no", and a "true" will automatically be typecasted to a "yes".

type
  TExtBool    = (no, yes, other);
  TPExtBool   = ^TExtBool;

  TSExtBool   = set of TExtBool;
  TPSExtBool  = ^TSExtBool;

  TAExtBool   = array [0..maxInt-1] of TExtBool;
  TPAExtBool  = ^TAExtBool;

  TDAExtBool  = array of TExtBool;
  TPDAExtBool = ^TDAExtBool;