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The range of values for integers in SXEmacs Lisp is -134217728 to
134217727 (28 bits; i.e.,
to
on most machines. (Some machines, in particular 64-bit machines such as
the DEC Alpha, may provide a wider range.) It is important to note that
the XEmacs Lisp arithmetic functions do not check for overflow. Thus
(1+ 134217727)
is -134217728 on most machines. (However,
you will get an error if you attempt to read an out-of-range
number using the Lisp reader.)
The read syntax for integers is a sequence of (base ten) digits with an optional sign at the beginning. (The printed representation produced by the Lisp interpreter never has a leading ‘+’.)
-1 ; The integer -1. 1 ; The integer 1. +1 ; Also the integer 1. 268435457 ; Causes an error on a 28-bit implementation.
See Numbers, for more information.