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Version: Sprint 4

setblank

Defines the blank symbol - the symbol that fills empty tape cells.

Syntax​

setblank(symbol);

Parameters​

  • symbol: A single character to use as the blank symbol

Default​

If not specified, the blank symbol defaults to _ (underscore).

Examples​

setblank(_);
setblank(#);
setblank( );  ### Space as blank

Rules​

  • Takes exactly one argument
  • Can only be declared once
  • Must be a single character
  • Should typically be included in the alphabet (though not required)

Examples​

Using default blank:

setvariant(single-tape);
setalpha(0, 1);
### blank is automatically '_'

Custom blank symbol:

setvariant(single-tape);
setalpha(0, 1, #);
setblank(#);  ### '#' is now the blank symbol

Errors​

  • Wrong arity: 'setblank' takes exactly 1 argument, got 2
  • Duplicate: duplicate 'setblank'

See Also​