As with all compiler switch variables, the value of this variable
can be t, nil, or a
function object that accepts four arguments and returns t or nil. The arguments
passed to the function will be the values of the safety, space, speed,
and debug optimization qualities, in that order. nil is equivalent to a function that always returns
nil and t to a
function that always returns t. When we say
t (or true) or nil
(or false) in the text below, we mean that the function returns,
respectively, t or nil. If true, compiler will generate code that
assumes the sum and difference of declared fixnums are
fixnums. Initially true only if speed is 3 and safety is 0.
Warning: if this switch returns true during compilation but the sum or difference of two declared fixnums is not a fixnum, the compiled code will silently produce erroneous results.
See compiling.htm for information on the compiler.
The documentation is described in introduction.htm and the index is in index.htm.
Copyright (c) 1998-2000, Franz Inc. Berkeley, CA., USA. All rights reserved.
Created 2000.10.5.