Short Common Lisp Reference List

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Short Common Lisp Reference List

;;;; four semicolons                     headline
;;; three semicolons                     left justified comment
;; two semicolons                        comment on a new line indented in accordance with the program text

(.......) ; one semicolon the comment is written to the right of the program text

Function definition

(defun name (parameters) {documentation} definition)

Example

(defun foo(x) "prints the value of the argument" (print x) ) ;foo

Arithmetic functions

(+ x1 ... xn)	addition
(* x1 ... xn)	multiplication
(- x1 ... xn)	subtraction
(/ x1 ... xn)	division
(1+ x)	increment with 1
(1- x)	decrement with 1
(expt x n)	x raised to power n
(exp n)	e raised to power n
(sqrt x)	square root
(abs x)	absolute value
(max x1 ... xn)	max value
(min x1 ... xn)	min value
(float x)	convert integer (or rational) to float
(truncate x)	truncate integer
(round x)	round floating number
(mod x y)	modulus
(rem x y)	remainder

Assignment

(setq symbol value)	symbol is assigned value
(setf place value)	object at place is assigned value

Predicates (numbers)

(< x1 ... xn)	less ?
(<= x1 ... xn)	less or equal ?
(> x1 ... xn)	greater ?
(>= x1 ... xn)	greater or equal ?
(= x1 ... xn)	equal ?
(/= x1 ... xn)	not equal ?

Predicates (type tests)

(zerop x)	0 ?
(plusp x)	> 0 ?
(minusp x)	< 0 ?
(oddp x)	odd ?
(evenp x)	even ?
(numberp x)	number ?
(integerp x)	integer ?
(floatp x)	floating ?
(rationalp x)	rational ?
(complexp x)	complex ?
(symbolp x)	symbol ?
(consp x)	cons ?
(listp x)	list ?
(atom x)	atom ?
(null x)	nil ?
(endp l)	is the list l the empty list (nil)?

Equal tests

(eq s1 s2)	;are the symbols s1 and s2 equal?
(= n1 n2)	;are the numbers n1 and n2 equal?
(eql x1 x2)	;are (the symbols, numbers, characters) x1 and x2 equal?
(equal obj1 obj2)	;are the objects obj1 and obj2 equal?

Output functions

(princ x stream)	;sends x to stream without special characters
(prin1 x stream)	;sends x to stream with special characters
(terpri stream)	;sends new-line to stream
(fresh-line stream)	;sends new-line to stream if not already at a new line
(print x stream)	;sends x and new-line to stream with special characters
(write x stream options)	;a printed representation of x is output
(error string obj-1 ... obj-n)	;a fatal error is signalled, format is applied and sent to the error handling mechanism
(format string obj-1 ... obj-n) ~a the object is printed as by princ ~d the object is printed in decimal radix ~e the object is printed as a floating-point number using exponential notation ~f the object is printed as a floating-point number with decimal digits ~s the object is printed as by prin1 ~t tabulator ~% new-line ~& new-line if not at the beginning of a new line ~\| new page	;the printed representation of the objects is output in accordance with the format specified in string

Input functions

(read stream)	;reads a Lisp object from stream
(read-char stream)	;reads a character from stream
(read-line stream)	;reads a line fromstream
(peek-char peek-type stream)	;the next character from stream is read, but not removed - if peek-type is T white space is skipped

Array structures

(make-array size)	;creates an array with size elements
(make-array rank)	;creates a multi-dimensional array, rank is a list indicating the size of the dimensions
(vector e-1 ... e-n)	;creates a vector consisting of the elements e-i
(arrayp obj)	;test if obj is an array structure
(aref arr ix-1 ... ix-n)	;returns the value of the element at ix-1 ... ix-n inarr
(setf (aref arr ix1 ... ixn) element)	;stores element at at ix-1 ... ix-n in arr
(array-rank arr)	;returns the number of dimensions of arr

Record structures

(defstruct name {docstring} slot-name-1 ... slot-name-n)
(defstruct name {docstring} (slot-name-1 default-1))... (slot-name-n default-n))
(make-name :slot-name-1 expr-1 ... :slot-name-n expr-n)	;creates a record structure
(name-slot-name record)	;returns the value of the slot-name element in record
(setf (name-slot-name record) new-value)	;stores new -value in slot-name of record
(name-p record)	;is record a name-structure?
(copy-name record)	;creates a copy of record

Property lists

(get symbol property)	;returns the value associated with property from the property list of symbol
(remprop symbol property)	;removes property from the property list of symbol
(setf (get symbol property) value)	;associatesvalue to property in the property list of symbol
(symbol-plist symbol)	;returns the property list ofsymbol
(progn uttryck1 ... uttryckn)	;evaluatesexpr-11 ... expr-n sequentially, returns the value of expr-n
(prog1 uttryck1 ... uttryckn)	;evaluatesexpr-11 ... expr-n sequentially, returns the value of expr-1

Conditional expressions

(cond
    (test-1 consequent-1-1 consequent-1-2 ...)
    (test-2)
    (test-1 consequent-1-3)
    ...
    (test-nconsequent-1-n)
    )

(if test
    then-expression
    {else-expression}
    )

(case value
    (alt-1 expr-1 ... expr-n)
    ...
    (alt-n expr-1 ... expr-n)
    (otherwise expr)
    )

(when test
    expr-1
    ...
    expr-n
    )

;evaluate expr-1 ... expr-n if test is true

(unless test
    expr-1
    ...
    expr-n
    )

;do not evaluate expr-1 ... expr-n if test is true

Repetition

(loop
    expr-1
    ...
    expr-n
    )

;infinite repetition - terminated by (return value)

(dolist (var list-form {result})
    {declarations}
    expr-1
    ...
    expr-n
    )

(dotimes (var count-form {result})
    {declarations}
    expr-1
    ...
    expr-n
    )

(do (var {init-form {repetition-form}})
    {test result-form}
    {declarations}
    expr-1
    ...
    expr-n
    )

Blocks

(block block-name
    expr-1
    ...
    expr-n
    )

(return-from block-name value)

;return from named block

(return value)

;return from implicit block

List Predicates

(member obj l)

;is the object obj a (top-level) member of list l ?

List functions

(car l)	;the first element in the list l
(cdr l)	;the list l , except the first element
(first l)	;the first element in the list l
(second l)	;the second element in the list l
...
(tenth l)	;the tenth element in the list l
(nth number l)	;the number-th element in the list l
(last l)	;the last element in the list l
(rest l)	;the list l , except the first element
(cons obj-1 obj-2)	;the cons whose car is obj-1 and whose cdr is obj-2
(list obj-1 ... obj-n)	;creates a list of the objects
(append l-1 ... l-n)	;joins the elements of the lists into a single list
(make-list size :initial-element x)	;creates a list with size elements initiated to x
(copy-list l)	;creates a copy of l
(remove s l)	;creates a copy of l , with all s elements removed
(reverse l)	;creates a reversed copy of l
(subst new old l)	;creates a copy of l
(intersection l1 l2)	;creates a list consisting of all elements that are
(union l1 l2)	;creates a list consisting of all elements in either of the lists
(butlast l)	;creates a list of the elements in l, except the last element
(length l)	;length of list l
(assoc key alist)	;returns the first top level element of alist whose car equals key

Map functions

(mapcar fn list1 ... listn)

;applies fn to the elements in the list(s), returns the values in a list

(maplist fn liist-1 ... list-n)

;applies fn applicerar fn to the tails of the list(s), returns the values in a list

Let

(let
    (
        (var-1 {init-1})
        ...
        (var-n {init-n})
        )
    expr-1
    ...
    expr-n
    )

Labels

(labels
    (
        (fn-1 argument-1 definition-1)
        ...
        (fn-n argument-n definition-n)
        )
    expr-1
    ...
    expr-n
    )

Last changed 1996-11-08, Eric Astor