Three dogs (Are there three dogs or one dog?) is a code snippet used to illustrate the lettercase sensitivity of the programming language. For a case-sensitive language, the identifiers dog, Dog and DOG are all different and we should get the output:

The three dogs are named Benjamin, Samba and Bernie.

For a language that is lettercase insensitive, we get the following output:

There is just one dog named Bernie.



Related task

 Unicode variable names


*process or(!) source xref attributes macro options;
 /*********************************************************************
 * Program to show that PL/I is case-insensitive
 * 28.05.2013 Walter Pachl
 *********************************************************************/
 case: proc options(main);
 Dcl dog Char(20) Var;
 dog = "Benjamin";
 Dog = "Samba";
 DOG = "Bernie";
 Put Edit(dog,Dog,DOG)(Skip,3(a,x(1)));
 End;