up previous next
protect a variable from being overwritten
protect X : reason;
where reason: STRING
This command protects the variable
from being assigned to.
Attempting to assign to it will produce an error; if a
(STRING) was given it is printed in the error message.
/**/ MaxSize := 99;
/**/ protect MaxSize : "size limit for fast computation";
-- /**/ MaxSize := 1000; --> !!! ERROR !!! as expected
ERROR: Cannot set "MaxSize" (size limit for fast computation)
/**/ unprotect MaxSize; --> remove protection, X may be assigned to now
/**/ MaxSize := 1000; --> OK