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Alexandria software and associated documentation are in the public domain:
Authors dedicate this work to public domain, for the benefit of the public at large and to the detriment of the authors’ heirs and successors. Authors intends this dedication to be an overt act of relinquishment in perpetuity of all present and future rights under copyright law, whether vested or contingent, in the work. Authors understands that such relinquishment of all rights includes the relinquishment of all rights to enforce (by lawsuit or otherwise) those copyrights in the work.
Authors recognize that, once placed in the public domain, the work may be freely reproduced, distributed, transmitted, used, modified, built upon, or otherwise exploited by anyone for any purpose, commercial or non-commercial, and in any way, including by methods that have not yet been invented or conceived.
In those legislations where public domain dedications are not recognized or possible, Alexandria is distributed under the following terms and conditions:
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
Unless otherwise noted, the symbols are exported from
the "ALEXANDRIA" package; only newer symbols
that require "ALEXANDRIA-2" are fully qualified.
The package "ALEXANDRIA-2" includes all the symbols
from "ALEXANDRIA-1".
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Like gethash, but if key is not found in the hash-table saves the default
under key before returning it. Secondary return value is true if key was
already in the table.
Returns a copy of hash table table, with the same keys and values
as the table. The copy has the same properties as the original, unless
overridden by the keyword arguments.
Before each of the original values is set into the new hash-table, key
is invoked on the value. As key defaults to cl:identity, a shallow
copy is returned by default.
Like maphash, but calls function with each key in the hash table table.
Like maphash, but calls function with each value in the hash table table.
Returns a list containing the keys of hash table table.
Returns a list containing the values of hash table table.
Returns an association list containing the keys and values of hash table
table.
Returns a property list containing the keys and values of hash table
table.
Returns a hash table containing the keys and values of the association list
alist. Hash table is initialized using the hash-table-initargs.
Returns a hash table containing the keys and values of the property list
plist. Hash table is initialized using the hash-table-initargs.
Next: Conses, Previous: Hash Tables, Up: Alexandria [Contents]
Ensures that the global variable named by name is a constant with a value
that is equal under test to the result of evaluating initial-value. test is a
/function designator/ that defaults to eql. If documentation is given, it
becomes the documentation string of the constant.
Signals an error if name is already a bound non-constant variable.
Signals an error if name is already a constant variable whose value is not
equal under test to result of evaluating initial-value.
destructuring-case, -ccase, and -ecase are a combination of case and destructuring-bind.
keyform must evaluate to a cons.
Clauses are of the form:
((CASE-KEYS . DESTRUCTURING-LAMBDA-LIST) FORM*)
The clause whose case-keys matches car of key, as if by case, ccase, or ecase,
is selected, and FORMs are then executed with cdr of key is destructured and
bound by the destructuring-lambda-list.
Example:
(defun dcase (x)
(destructuring-case x
((:foo a b)
(format nil "foo: ~S, ~S" a b))
((:bar &key a b)
(format nil "bar: ~S, ~S" a b))
(((:alt1 :alt2) a)
(format nil "alt: ~S" a))
((t &rest rest)
(format nil "unknown: ~S" rest))))
(dcase (list :foo 1 2)) ; => "foo: 1, 2" (dcase (list :bar :a 1 :b 2)) ; => "bar: 1, 2" (dcase (list :alt1 1)) ; => "alt: 1" (dcase (list :alt2 2)) ; => "alt: 2" (dcase (list :quux 1 2 3)) ; => "unknown: 1, 2, 3"
(defun decase (x)
(destructuring-case x
((:foo a b)
(format nil "foo: ~S, ~S" a b))
((:bar &key a b)
(format nil "bar: ~S, ~S" a b))
(((:alt1 :alt2) a)
(format nil "alt: ~S" a))))
(decase (list :foo 1 2)) ; => "foo: 1, 2" (decase (list :bar :a 1 :b 2)) ; => "bar: 1, 2" (decase (list :alt1 1)) ; => "alt: 1" (decase (list :alt2 2)) ; => "alt: 2" (decase (list :quux 1 2 3)) ; =| error
Multiple-place modify macro for ensure-function: ensures that each of
places contains a function.
Evaluates first-form, then second-form, and then forms. Yields as its value
all the value returned by second-form.
Expands into a lambda-expression within whose body name denotes the
corresponding function.
Evaluates form arguments one at a time, until the nth-value returned by one
of the forms is true. It then returns all the values returned by evaluating
that form. If none of the forms return a true nth value, this form returns
nil.
Creates new variable bindings, and conditionally executes either
then-form or else-form. else-form defaults to nil.
bindings must be either single binding of the form:
(variable initial-form)
or a list of bindings of the form:
((variable-1 initial-form-1) (variable-2 initial-form-2) ... (variable-n initial-form-n))
All initial-forms are executed sequentially in the specified order. Then all the variables are bound to the corresponding values.
If all variables were bound to true values, the then-form is executed with the
bindings in effect, otherwise the else-form is executed with the bindings in
effect.
Creates new variable bindings, and conditionally executes forms.
bindings must be either single binding of the form:
(variable initial-form)
or a list of bindings of the form:
((variable-1 initial-form-1) (variable-2 initial-form-2) ... (variable-n initial-form-n))
All initial-forms are executed sequentially in the specified order. Then all the variables are bound to the corresponding values.
If all variables were bound to true values, then forms are executed as an
implicit progn.
Creates new variable bindings, and conditionally executes body.
bindings must be either single binding of the form:
(variable initial-form)
or a list of bindings of the form:
((variable-1 initial-form-1) (variable-2 initial-form-2) ... (variable-n initial-form-n))
Each initial-form is executed in turn, and the variable bound to the
corresponding value. initial-form expressions can refer to variables
previously bound by the when-let*.
Execution of when-let* stops immediately if any initial-form evaluates to nil.
If all INITIAL-FORMs evaluate to true, then body is executed as an implicit
progn.
Evaluates first matching clause, returning its values, or evaluates and
returns the values of t or otherwise if no keys match.
Like switch, but signals a continuable error if no key matches.
Like switch, but signals an error if no key matches.
Evaluates exactly one of possibilities, chosen at random.
Evaluates its arguments one at a time, from left to right. If more than one
argument evaluates to a true value no further datums are evaluated, and nil is
returned as both primary and secondary value. If exactly one argument
evaluates to true, its value is returned as the primary value after all the
arguments have been evaluated, and t is returned as the secondary value. If no
arguments evaluate to true nil is returned as primary, and t as secondary
value.
Returns a function that applies each of predicate and more-predicate
functions in turn to its arguments, returning the primary value of the first
predicate that returns true, without calling the remaining predicates.
If none of the predicates returns true, nil is returned.
Returns a function that applies each of predicate and more-predicate
functions in turn to its arguments, returning nil if any of the predicates
returns false, without calling the remaining predicates. If none of the
predicates returns false, returns the primary value of the last predicate.
Returns a function composed of function and more-functions that applies its
arguments to to each in turn, starting from the rightmost of more-functions,
and then calling the next one with the primary value of the last.
Returns the function designated by function-designator:
if function-designator is a function, it is returned, otherwise
it must be a function name and its fdefinition is returned.
Returns a function composed of function and more-functions that applies
its arguments to each in turn, starting from the rightmost of
more-functions, and then calling the next one with all the return values of
the last.
Returns a function that applies arguments and the arguments
it is called with to function.
Returns a function that applies the arguments it is called
with and arguments to function.
Lines up forms elements as the first argument of their successor.
Example:
(line-up-first 5 (+ 20) / (+ 40))
is equivalent to:
(+ (/ (+ 5 20)) 40)
Note how the single ’/ got converted into a list before threading.
Lines up forms elements as the last argument of their successor.
Example:
(line-up-last 5 (+ 20) / (+ 40))
is equivalent to:
(+ 40 (/ (+ 20 5)))
Note how the single ’/ got converted into a list before threading.
Next: Sequences, Previous: Data and Control Flow, Up: Alexandria [Contents]
Type designator for proper lists. Implemented as a satisfies type, hence
not recommended for performance intensive use. Main usefullness as a type
designator of the expected type in a type-error.
Type designator for circular lists. Implemented as a satisfies type, so not
recommended for performance intensive use. Main usefullness as the
expected-type designator of a type-error.
Modify-macro for append. Appends lists to the place designated by the first
argument.
Modify-macro for nconc. Concatenates lists to place designated by the first
argument.
Modify macro for remove-from-plist.
Modify macro for delete-from-plist.
Modify-macro for reverse. Copies and reverses the list stored in the given
place and saves back the result into the place.
Modify-macro for nreverse. Reverses the list stored in the given place by
destructively modifying it and saves back the result into the place.
Modify-macro for union. Saves the union of list and the contents of the
place designated by the first argument to the designated place.
Modify-macro for nunion. Saves the union of list and the contents of the
place designated by the first argument to the designated place. May modify
either argument.
Iterates over elements of plist. body can be preceded by
declarations, and is like a tagbody. return may be used to terminate
the iteration early. If return is not used, returns values.
Returns true if object is a circular list, nil otherwise.
Returns true if object is a circular tree, nil otherwise.
Returns true if object is a proper list.
Returns a property list containing the same keys and values as the
association list alist in the same order.
Returns an association list containing the same keys and values as the
property list plist in the same order.
Creates a circular list of elements.
Creates a circular list of length with the given initial-element.
If thing is a cons, its car is returned. Otherwise thing is returned.
If cons is a cons, it is returned. Otherwise returns a fresh cons with cons
in the car, and nil in the cdr.
If list is a list, it is returned. Otherwise returns the list designated by list.
Traverses the tree in order, collecting non-null leaves into a list.
Returns the last element of list. Signals a type-error if list is not a
proper list.
Sets the last element of list. Signals a type-error if list is not a proper
list.
Returns length of list, signalling an error if it is not a proper list.
Applies function to respective element(s) of each list, appending all the
all the result list to a single list. function must return a list.
Returns a list containing the results of calling function with one argument
from list, and one from each of more-lists for each combination of arguments.
In other words, returns the product of list and more-lists using function.
Example:
(map-product 'list '(1 2) '(3 4) '(5 6))
=> ((1 3 5) (1 3 6) (1 4 5) (1 4 6)
(2 3 5) (2 3 6) (2 4 5) (2 4 6))
Returns a property-list with same keys and values as plist, except that keys
in the list designated by keys and values corresponding to them are removed.
The returned property-list may share structure with the plist, but plist is
not destructively modified. Keys are compared using eq.
Just like remove-from-plist, but this version may destructively modify the
provided plist.
Just like remove-from-plist, but this version may destructively modify the
provided plist.
The second return value is an alist of the removed items, in unspecified order.
Returns true if every element of list1 matches some element of list2 and
every element of list2 matches some element of list1. Otherwise returns false.
Returns true if object is a list that denotes a set, nil otherwise. A list
denotes a set if each element of the list is unique under key and test.
Next: IO, Previous: Conses, Up: Alexandria [Contents]
Type designator for proper sequences, that is proper lists and sequences that are not lists.
Modify-macro for delete. Sets place designated by the first argument to
the result of calling delete with item, place, and the keyword-arguments.
Modify-macro for remove. Sets place designated by the first argument to
the result of calling remove with item, place, and the keyword-arguments.
Returns a sequence of the same type as sequence, with the elements of
sequence rotated by n: n elements are moved from the end of the sequence to
the front if n is positive, and -n elements moved from the front to the end if
n is negative. sequence must be a proper sequence. n must be an integer,
defaulting to 1.
If absolute value of n is greater then the length of the sequence, the results
are identical to calling rotate with
(* (signum n) (mod n (length sequence))).
Note: the original sequence may be destructively altered, and result sequence may share structure with it.
Returns a random permutation of sequence bounded by start and end.
Original sequence may be destructively modified.
Signals an error if sequence is not a proper sequence.
Returns a random element from sequence bounded by start and end. Signals an
error if the sequence is not a proper non-empty sequence, or if end and start
are not proper bounding index designators for sequence.
Returns t if sequence is an empty sequence and nil
otherwise. Signals an error if sequence is not a sequence.
Return true if sequence is a sequence of length length. Signals an error if
sequence is not a sequence. Returns false for circular lists.
Takes any number of sequences or integers in any order. Returns true iff the length of all the sequences and the integers are equal. Hint: there’s a compiler macro that expands into more efficient code if the first argument is a literal integer.
Returns a fresh sequence of type, which has the same elements as
sequence.
Returns the first element of sequence. Signals a type-error if sequence is
not a sequence, or is an empty sequence.
Sets the first element of sequence. Signals a type-error if sequence is
not a sequence, is an empty sequence, or if object cannot be stored in sequence.
Returns the last element of sequence. Signals a type-error if sequence is
not a proper sequence, or is an empty sequence.
Sets the last element of sequence. Signals a type-error if sequence is not a proper
sequence, is an empty sequence, or if object cannot be stored in sequence.
Returns true if sequence is a sequence whose first element is eql to object.
Returns nil if the sequence is not a sequence or is an empty sequence.
Test whether the first elements of sequence are the same (as per TEST) as the elements of prefix.
If return-suffix is t the function returns, as a second value, a
sub-sequence or displaced array pointing to the sequence after prefix.
Returns true if sequence is a sequence whose last element is eql to object.
Returns nil if the sequence is not a sequence or is an empty sequence. Signals
an error if sequence is an improper list.
Test whether sequence ends with suffix. In other words: return true if
the last (length SUFFIX) elements of sequence are equal to suffix.
Calls function with each combination of length constructable from the
elements of the subsequence of sequence delimited by start and end. start
defaults to 0, end to length of sequence, and length to the length of the
delimited subsequence. (So unless length is specified there is only a single
combination, which has the same elements as the delimited subsequence.) If
copy is true (the default) each combination is freshly allocated. If copy is
false all combinations are eq to each other, in which case consequences are
unspecified if a combination is modified by function.
Calls function with each derangement of the subsequence of sequence denoted
by the bounding index designators start and end. Derangement is a permutation
of the sequence where no element remains in place. sequence is not modified,
but individual derangements are eq to each other. Consequences are unspecified
if calling function modifies either the derangement or sequence.
Calls function with each permutation of length constructable
from the subsequence of sequence delimited by start and end. start
defaults to 0, end to length of the sequence, and length to the
length of the delimited subsequence.
Next: Macro Writing, Previous: Sequences, Up: Alexandria [Contents]
Return the "content" of stream as a fresh string.
Return the contents of the file denoted by pathname as a fresh string.
The external-format parameter will be passed directly to with-open-file
unless it’s nil, which means the system default.
Return "content" of stream as freshly allocated (unsigned-byte 8) vector.
Read pathname into a freshly allocated (unsigned-byte 8) vector.
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Constructs code whose primary goal is to help automate the handling of multiple evaluation within macros. Multiple evaluation is handled by introducing intermediate variables, in order to reuse the result of an expression.
The returned value is a list of the form
(let ((<gensym-1> <expr-1>)
...
(<gensym-n> <expr-n>))
<res>)
where gensym-1, ..., gensym-n are the intermediate variables introduced in order
to evaluate expr-1, ..., expr-n once, only. res is code that is the result of
evaluating the implicit progn forms within a special context determined by
specs. res should make use of (reference) the intermediate variables.
Each element within specs is either a symbol symbol or a pair (SYMBOL INITFORM).
Bare symbols are equivalent to the pair (SYMBOL SYMBOL).
Each pair (SYMBOL INITFORM) specifies a single intermediate variable:
initform is an expression evaluated to produce EXPR-i
symbol is the name of the variable that will be bound around forms to the
corresponding gensym GENSYM-i, in order for forms to generate res that
references the intermediate variable
The evaluation of INITFORMs and binding of SYMBOLs resembles let. INITFORMs of
all the pairs are evaluated before binding SYMBOLs and evaluating forms.
Example:
The following expression
(let ((x '(incf y)))
(once-only (x)
`(cons ,x ,x)))
;;; => ;;; (let ((#1=#:X123 (incf y))) ;;; (cons #1# #1#))
could be used within a macro to avoid multiple evaluation like so
(defmacro cons1 (x)
(once-only (x)
`(cons ,x ,x)))
(let ((y 0))
(cons1 (incf y)))
;;; => (1 . 1)
Example:
The following expression demonstrates the usage of the initform field
(let ((expr '(incf y)))
(once-only ((var `(1+ ,expr)))
`(list ',expr ,var ,var)))
;;; => ;;; (let ((#1=#:VAR123 (1+ (incf y)))) ;;; (list '(incf y) #1# #1))
which could be used like so
(defmacro print-succ-twice (expr)
(once-only ((var `(1+ ,expr)))
`(format t "Expr: ~s, Once: ~s, Twice: ~s~%" ',expr ,var ,var)))
(let ((y 10))
(print-succ-twice (incf y)))
;;; >> ;;; Expr: (INCF Y), Once: 12, Twice: 12
Binds a set of variables to gensyms and evaluates the implicit progn forms.
Each element within names is either a symbol symbol or a pair (SYMBOL
STRING-DESIGNATOR). Bare symbols are equivalent to the pair (SYMBOL SYMBOL).
Each pair (SYMBOL STRING-DESIGNATOR) specifies that the variable named by symbol
should be bound to a symbol constructed using gensym with the string designated
by string-designator being its first argument.
Alias for with-gensyms.
Returns t if the argument matches the state of the *features*
list and nil if it does not. feature-expression can be any atom
or list acceptable to the reader macros #+ and #-.
Parses body into (values remaining-forms declarations doc-string).
Documentation strings are recognized only if documentation is true.
Syntax errors in body are signalled and whole is used in the signal
arguments when given.
Parses an ordinary lambda-list, returning as multiple values:
1. Required parameters.
2. Optional parameter specifications, normalized into form:
(name init suppliedp)
3. Name of the rest parameter, or nil.
4. Keyword parameter specifications, normalized into form:
((keyword-name name) init suppliedp)
5. Boolean indicating &allow-other-keys presence.
6. &aux parameter specifications, normalized into form
(name init).
7. Existence of &key in the lambda-list.
Signals a program-error is the lambda-list is malformed.
Next: Arrays, Previous: Macro Writing, Up: Alexandria [Contents]
Returns a symbol with name designated by name, accessible in package
designated by package. If symbol is not already accessible in package, it is
interned there. Returns a secondary value reflecting the status of the symbol
in the package, which matches the secondary return value of intern.
Example:
(ensure-symbol :cons :cl) => cl:cons, :external
Constructs a string by applying arguments to string designator control as
if by format within with-standard-io-syntax, and then creates a symbol named
by that string.
If package is nil, returns an uninterned symbol, if package is t, returns a
symbol interned in the current package, and otherwise returns a symbol
interned in the package designated by package.
Interns the string designated by name in the keyword package.
If name is a non-negative integer, calls gensym using it. Otherwise name
must be a string designator, in which case calls gensym using the designated
string as the argument.
Returns a list of length gensyms, each generated as if with a call to make-gensym,
using the second (optional, defaulting to "G") argument.
Concatenate together the names of some strings and symbols, producing a symbol in the current package.
Next: Types, Previous: Symbols, Up: Alexandria [Contents]
Type designator for an index into array of length: an integer between
0 (inclusive) and length (exclusive). length defaults to one less than
array-dimension-limit.
Type designator for a dimension of an array of length: an integer between
0 (inclusive) and length (inclusive). length defaults to one less than
array-dimension-limit.
Returns an undisplaced copy of array, with same fill-pointer and
adjustability (if any) as the original, unless overridden by the keyword
arguments.
Next: Numbers, Previous: Arrays, Up: Alexandria [Contents]
A string designator type. A string designator is either a string, a symbol, or a character.
Modify-macro for coerce.
Returns a function of one argument, which returns true when its argument is
of type.
Returns a primary value of t is type1 and type2 are the same type,
and a secondary value that is true is the type equality could be reliably
determined: primary value of nil and secondary value of t indicates that the
types are not equivalent.
Previous: Types, Up: Alexandria [Contents]
Modify-macro for max. Sets place designated by the first argument to the
maximum of its original value and numbers.
Modify-macro for min. Sets place designated by the first argument to the
minimum of its original value and numbers.
Binomial coefficient of n and k, also expressed as n choose k. This is the
number of k element combinations given n choises. n must be equal to or
greater then k.
Number of k element permutations for a sequence of n objects.
k defaults to n
Clamps the number into [min, max] range. Returns min if number is lesser then
min and max if number is greater then max, otherwise returns number.
Returns the result of linear interpolation between A and b, using the
interpolation coefficient v.
Factorial of non-negative integer n.
Subfactorial of the non-negative integer n.
Returns two gaussian random double floats as the primary and secondary value,
optionally constrained by min and max. Gaussian random numbers form a standard
normal distribution around 0.0d0.
Sufficiently positive min or negative max will cause the algorithm used to
take a very long time. If min is positive it should be close to zero, and
similarly if max is negative it should be close to zero.
Return a list of n numbers, starting from start (with numeric contagion
from step applied), each consequtive number being the sum of the previous one
and step. start defaults to 0 and step to 1.
Examples:
(iota 4) => (0 1 2 3) (iota 3 :start 1 :step 1.0) => (1.0 2.0 3.0) (iota 3 :start -1 :step -1/2) => (-1 -3/2 -2)
Calls function with n numbers, starting from start (with numeric contagion
from step applied), each consequtive number being the sum of the previous one
and step. start defaults to 0 and step to 1. Returns n.
Examples:
(map-iota #'print 3 :start 1 :step 1.0) => 3
;;; 1.0
;;; 2.0
;;; 3.0
Returns the mean of sample. sample must be a sequence of numbers.
Returns median of sample. sample must be a sequence of real numbers.
Variance of sample. Returns the biased variance if biased is true (the default),
and the unbiased estimator of variance if biased is false. sample must be a
sequence of numbers.
Standard deviation of sample. Returns the biased standard deviation if
biased is true (the default), and the square root of the unbiased estimator
for variance if biased is false (which is not the same as the unbiased
estimator for standard deviation). sample must be a sequence of numbers.