zl:1 - FTP

integerp
276
(defun trailing-zeros (integer)
(1- (integer-length (logand integer (- integer»»)
(trailing-zeros 0) => -1
iii An adequate result since there are an undefined amount
iii of trailing zeros in 0
(trailing-zeros 1) => 0
(trailing-zeros 4) => 2
(trailing-zeros 9) => 0
; 4 is #b100
i 9 is #b1001
For a table of related items: See the section "Functions Returning Components
or Characteristics of Argument" in Symbolics Common Lisp: Language
Concepts.
integerp object Function
The predicate integerp is true if its argument is an integer; it is false,
otherwise.
Examples:
(integerp 7) => T
(integerp 4.0) => NIL
(integerp #c(2 0» => T i#c(2 0) is coerced to an integer
(integerp "not a number") => NIL
For a table of related items: See the section "Numeric Type-checking
Predicates" in Symbolics Common Lisp: Language Concepts.
intern string &optional (Pkg zl:package) Function
Finds or creates a symbol named string in pkg. Inherited symbols in pkg
are included in the search for a symbol named string. If a symbol named
string is found, it is returned. If no such symbol is found, one is created
and installed in pkg as an internal symbol (if pkg is the keyword package,
the symbol is installed as an external symbol).
intern returns two values. The first is the symbol that was found or
created. The second value is nil for newly created symbols. If the symbol
returned is a pre-existing symbol, this second value is one of the following:
: internal
: external
: inherited
The symbol is present in pkg as an internal symbol.
The symbol is present in pkg as an external symbol.
The symbol is an internal symbol in pkg inherited by way
of use-package.
For more information: See the section "Mapping Names to Symbols" in
Symbolics Common Lisp: Language Concepts.