Hemlock variables supply a simple customization mechanism by permitting commands to be parameterized. For details See vars.
The name of this variable is Sample Variable and its initial value is 36.
This variable sets a lower limit on the number of replacements that be done by Sample Command. If the prefix argument is supplied, and smaller in absolute value than Sample Variable, then the user is prompted as to whether that small a number of occurrences should be replaced, so as to avoid a possibly disastrous error.