clojure.core

#""

Regex literal. #"pattern" compiles to java.util.regex.Pattern at read time.

#'

Var quote. #'foo resolves to the Var object itself.

#()

Anonymous function shorthand. #(+ %1 %2) expands to (fn [x y] (+ x y)).

#?

Reader conditional. #?(:clj expr :cljs expr) for .cljc files.

#?@

Splicing reader conditional.

#_

Discard. #_form causes the reader to ignore the next form.

#inst

Tagged literal for instants. #inst "2024-01-01".

#uuid

Tagged literal for UUIDs.

#{}

Set literal. #{1 2 3} creates a persistent hash set.

'

Quote. 'form expands to (quote form).

*

Returns the product of nums. (*) returns 1. Does not auto-promote longs, will throw on overflow. See also: *'

*'

Returns the product of nums. (*') returns 1. Supports arbitrary precision. See also: *

*1

bound in a repl thread to the most recent value printed

*2

bound in a repl thread to the second most recent value printed

*3

bound in a repl thread to the third most recent value printed

*agent*

The agent currently running an action on this thread, else nil

*allow-unresolved-vars*

*assert*

When set to logical false, 'assert' will omit assertion checks in compiled code. Defaults to true.

*clojure-version*

The version info for Clojure core, as a map containing :major :minor :incremental and :qualifier keys. Feature releas...

*command-line-args*

A sequence of the supplied command line arguments, or nil if none were supplied

*compile-files*

Set to true when compiling files, false otherwise.

*compile-path*

Specifies the directory where 'compile' will write out .class files. This directory must be in the classpath for 'comp...

*compiler-options*

A map of keys to options. Note, when binding dynamically make sure to merge with previous value. Supported options: ...

*data-readers*

Map from reader tag symbols to data reader Vars. When Clojure starts, it searches for files named 'data_readers.clj' ...

*default-data-reader-fn*

When no data reader is found for a tag and *default-data-reader-fn* is non-nil, it will be called with two arguments, ...

*e

bound in a repl thread to the most recent exception caught by the repl

*err*

A java.io.Writer object representing standard error for print operations. Defaults to System/err, wrapped in a PrintW...

*file*

The path of the file being evaluated, as a String. When there is no file, e.g. in the REPL, the value is not defined.

*flush-on-newline*

When set to true, output will be flushed whenever a newline is printed. Defaults to true.

*fn-loader*

*in*

A java.io.Reader object representing standard input for read operations. Defaults to System/in, wrapped in a LineNumb...

*math-context*

*ns*

A clojure.lang.Namespace object representing the current namespace.

*out*

A java.io.Writer object representing standard output for print operations. Defaults to System/out, wrapped in an Outp...

*print-dup*

When set to logical true, objects will be printed in a way that preserves their type when read in later. Defaults t...

*print-length*

*print-length* controls how many items of each collection the printer will print. If it is bound to logical false, the...

*print-level*

*print-level* controls how many levels deep the printer will print nested objects. If it is bound to logical false, th...

*print-meta*

If set to logical true, when printing an object, its metadata will also be printed in a form that can be read back by ...

*print-namespace-maps*

*print-namespace-maps* controls whether the printer will print namespace map literal syntax. It defaults to false, but...

*print-readably*

When set to logical false, strings and characters will be printed with non-alphanumeric characters converted to the ap...

*read-eval*

Defaults to true (or value specified by system property, see below) ***This setting implies that the full power of the...

*reader-resolver*

*repl*

Bound to true in a repl thread

*source-path*

*suppress-read*

*unchecked-math*

While bound to true, compilations of +, -, *, inc, dec and the coercions will be done without overflow checks. While b...

*use-context-classloader*

*verbose-defrecords*

*warn-on-reflection*

When set to true, the compiler will emit warnings when reflection is needed to resolve Java method calls or field acce...

+

Returns the sum of nums. (+) returns 0. Does not auto-promote longs, will throw on overflow. See also: +'

+'

Returns the sum of nums. (+') returns 0. Supports arbitrary precision. See also: +

-

If no ys are supplied, returns the negation of x, else subtracts the ys from x and returns the result. Does not auto-p...

-'

If no ys are supplied, returns the negation of x, else subtracts the ys from x and returns the result. Supports arbitr...

->

Threads the expr through the forms. Inserts x as the second item in the first form, making a list of it if it is not a...

->>

Threads the expr through the forms. Inserts x as the last item in the first form, making a list of it if it is not a ...

->ArrayChunk

Positional factory function for class clojure.core.ArrayChunk.

->Eduction

Positional factory function for class clojure.core.Eduction.

->Vec

Positional factory function for class clojure.core.Vec.

->VecNode

Positional factory function for class clojure.core.VecNode.

->VecSeq

Positional factory function for class clojure.core.VecSeq.

-cache-protocol-fn

-reset-methods

.

Host interop: field access or method call.

..

form => fieldName-symbol or (instanceMethodName-symbol args*) Expands into a member access (.) of the first member on...

/

If no denominators are supplied, returns 1/numerator, else returns numerator divided by all of the denominators.

<

Returns non-nil if nums are in monotonically increasing order, otherwise false.

<=

Returns non-nil if nums are in monotonically non-decreasing order, otherwise false.

=

Equality. Returns true if x equals y, false if not. Same as Java x.equals(y) except it also works for nil, and compare...

==

Returns non-nil if nums all have the equivalent value (type-independent), otherwise false

>

Returns non-nil if nums are in monotonically decreasing order, otherwise false.

>=

Returns non-nil if nums are in monotonically non-increasing order, otherwise false.

@

Deref. @ref expands to (deref ref).

abs

Returns the absolute value of a. If a is Long/MIN_VALUE => Long/MIN_VALUE If a is a double and zero => +0.0 If a i...

accessor

Returns a fn that, given an instance of a structmap with the basis, returns the value at the key. The key must be in ...

aclone

Returns a clone of the Java array. Works on arrays of known types.

add-tap

adds f, a fn of one argument, to the tap set. This function will be called with anything sent via tap>. This function ...

add-watch

Adds a watch function to an agent/atom/var/ref reference. The watch fn must be a fn of 4 args: a key, the reference, i...

agent

Creates and returns an agent with an initial value of state and zero or more options (in any order): :meta metadata...

agent-error

Returns the exception thrown during an asynchronous action of the agent if the agent is failed. Returns nil if the ag...

aget

Returns the value at the index/indices. Works on Java arrays of all types.

alength

Returns the length of the Java array. Works on arrays of all types.

alias

Add an alias in the current namespace to another namespace. Arguments are two symbols: the alias to be used, and the...

all-ns

Returns a sequence of all namespaces.

alter

Must be called in a transaction. Sets the in-transaction-value of ref to: (apply fun in-transaction-value-of-ref ar...

alter-meta!

Atomically sets the metadata for a namespace/var/ref/agent/atom to be: (apply f its-current-meta args) f must be f...

alter-var-root

Atomically alters the root binding of var v by applying f to its current value plus any args

amap

Maps an expression across an array a, using an index named idx, and return value named ret, initialized to a clone of ...

ancestors

Returns the immediate and indirect parents of tag, either via a Java type inheritance relationship or a relationship e...

and

Evaluates exprs one at a time, from left to right. If a form returns logical false (nil or false), and returns that va...

any?

Returns true given any argument.

apply

Applies fn f to the argument list formed by prepending intervening arguments to args.

areduce

Reduces an expression across an array a, using an index named idx, and return value named ret, initialized to init, se...

array-map

Constructs an array-map. If any keys are equal, they are handled as if by repeated uses of assoc.

as->

Binds name to expr, evaluates the first form in the lexical context of that binding, then binds name to that result, r...

aset

Sets the value at the index/indices. Works on Java arrays of reference types. Returns val.

aset-boolean

Sets the value at the index/indices. Works on arrays of boolean. Returns val.

aset-byte

Sets the value at the index/indices. Works on arrays of byte. Returns val.

aset-char

Sets the value at the index/indices. Works on arrays of char. Returns val.

aset-double

Sets the value at the index/indices. Works on arrays of double. Returns val.

aset-float

Sets the value at the index/indices. Works on arrays of float. Returns val.

aset-int

Sets the value at the index/indices. Works on arrays of int. Returns val.

aset-long

Sets the value at the index/indices. Works on arrays of long. Returns val.

aset-short

Sets the value at the index/indices. Works on arrays of short. Returns val.

assert

Evaluates expression x and throws an AssertionError with optional message if x does not evaluate to logical true. A...

assoc

assoc[iate]. When applied to a map, returns a new map of the same (hashed/sorted) type, that contains the mapping of...

assoc!

When applied to a transient map, adds mapping of key(s) to val(s). When applied to a transient vector, sets the val at...

assoc-in

Associates a value in a nested associative structure, where ks is a sequence of keys and v is the new value and return...

associative?

Returns true if coll implements Associative

atom

Creates and returns an Atom with an initial value of x and zero or more options (in any order): :meta metadata-map ...

await

Blocks the current thread (indefinitely!) until all actions dispatched thus far, from this thread or agent, to the age...

await-for

Blocks the current thread until all actions dispatched thus far (from this thread or agent) to the agents have occurre...

await1

bases

Returns the immediate superclass and direct interfaces of c, if any

bean

Takes a Java object and returns a read-only implementation of the map abstraction based upon its JavaBean properties.

bigdec

Coerce to BigDecimal

bigint

Coerce to BigInt

biginteger

Coerce to BigInteger

binding

binding => var-symbol init-expr Creates new bindings for the (already-existing) vars, with the supplied initial val...

bit-and

Bitwise and

bit-and-not

Bitwise and with complement

bit-clear

Clear bit at index n

bit-flip

Flip bit at index n

bit-not

Bitwise complement

bit-or

Bitwise or

bit-set

Set bit at index n

bit-shift-left

Bitwise shift left

bit-shift-right

Bitwise shift right

bit-test

Test bit at index n

bit-xor

Bitwise exclusive or

boolean

Coerce to boolean

boolean-array

Creates an array of booleans

boolean?

Return true if x is a Boolean

booleans

Casts to boolean[]

bound-fn

Returns a function defined by the given fntail, which will install the same bindings in effect as in the thread at the...

bound-fn*

Returns a function, which will install the same bindings in effect as in the thread at the time bound-fn* was called a...

bound?

Returns true if all of the vars provided as arguments have any bound value, root or thread-local. Implies that deref'...

bounded-count

If coll is counted? returns its count, else will count at most the first n elements of coll using its seq

butlast

Return a seq of all but the last item in coll, in linear time

byte

Coerce to byte

byte-array

Creates an array of bytes

bytes

Casts to bytes[]

bytes?

Return true if x is a byte array

case

Takes an expression, and a set of clauses. Each clause can take the form of either: test-constant result-expr (...

cast

Throws a ClassCastException if x is not a c, else returns x.

cat

A transducer which concatenates the contents of each input, which must be a collection, into the reduction.

catch

Catch clause inside try.

char

Coerce to char

char-array

Creates an array of chars

char-escape-string

Returns escape string for char or nil if none

char-name-string

Returns name string for char or nil if none

char?

Return true if x is a Character

chars

Casts to chars[]

chunk

chunk-append

chunk-buffer

chunk-cons

chunk-first

chunk-next

chunk-rest

chunked-seq?

class

Returns the Class of x

class?

Returns true if x is an instance of Class

clojure-version

Returns clojure version as a printable string.

coll?

Returns true if x implements IPersistentCollection

comment

Ignores body, yields nil

commute

Must be called in a transaction. Sets the in-transaction-value of ref to: (apply fun in-transaction-value-of-ref ar...

comp

Takes a set of functions and returns a fn that is the composition of those fns. The returned fn takes a variable numb...

comparator

Returns an implementation of java.util.Comparator based upon pred.

compare

Comparator. Returns a negative number, zero, or a positive number when x is logically 'less than', 'equal to', or 'gre...

compare-and-set!

Atomically sets the value of atom to newval if and only if the current value of the atom is identical to oldval. Retur...

compile

Compiles the namespace named by the symbol lib into a set of classfiles. The source for the lib must be in a proper ...

complement

Takes a fn f and returns a fn that takes the same arguments as f, has the same effects, if any, and returns the opposi...

completing

Takes a reducing function f of 2 args and returns a fn suitable for transduce by adding an arity-1 signature that call...

concat

Returns a lazy seq representing the concatenation of the elements in the supplied colls.

cond

Takes a set of test/expr pairs. It evaluates each test one at a time. If a test returns logical true, cond evaluates ...

cond->

Takes an expression and a set of test/form pairs. Threads expr (via ->) through each form for which the corresponding ...

cond->>

Takes an expression and a set of test/form pairs. Threads expr (via ->>) through each form for which the corresponding...

condp

Takes a binary predicate, an expression, and a set of clauses. Each clause can take the form of either: test-expr r...

conj

conj[oin]. Returns a new collection with the xs 'added'. (conj nil item) returns (item). (conj coll) returns col...

conj!

Adds x to the transient collection, and return coll. The 'addition' may happen at different 'places' depending on the ...

cons

Returns a new seq where x is the first element and seq is the rest.

constantly

Returns a function that takes any number of arguments and returns x.

construct-proxy

Takes a proxy class and any arguments for its superclass ctor and creates and returns an instance of the proxy.

contains?

Returns true if key is present in the given collection, otherwise returns false. Note that for numerically indexed co...

count

Returns the number of items in the collection. (count nil) returns 0. Also works on strings, arrays, and Java Collect...

counted?

Returns true if coll implements count in constant time

create-ns

Create a new namespace named by the symbol if one doesn't already exist, returns it or the already-existing namespace ...

create-struct

Returns a structure basis object.

cycle

Returns a lazy (infinite!) sequence of repetitions of the items in coll.

dec

Returns a number one less than num. Does not auto-promote longs, will throw on overflow. See also: dec'

dec'

Returns a number one less than num. Supports arbitrary precision. See also: dec

decimal?

Returns true if n is a BigDecimal

declare

defs the supplied var names with no bindings, useful for making forward declarations.

dedupe

Returns a lazy sequence removing consecutive duplicates in coll. Returns a transducer when no collection is provided.

def

Creates and interns a global var.

default-data-readers

Default map of data reader functions provided by Clojure. May be overridden by binding *data-readers*.

definline

Experimental - like defmacro, except defines a named function whose body is the expansion, calls to which may be expan...

definterface

Creates a new Java interface with the given name and method sigs. The method return types and parameter types may be s...

defmacro

Like defn, but the resulting function name is declared as a macro and will be used as a macro by the compiler when it ...

defmethod

Creates and installs a new method of multimethod associated with dispatch-value.

defmulti

Creates a new multimethod with the associated dispatch function. The docstring and attr-map are optional. Options a...

defn

Same as (def name (fn [params* ] exprs*)) or (def name (fn ([params* ] exprs*)+)) with any doc-string or attrs added...

defn-

same as defn, yielding non-public def

defonce

defs name to have the root value of the expr iff the named var has no root value, else expr is unevaluated

defprotocol

A protocol is a named set of named methods and their signatures: (defprotocol AProtocolName ;optional doc string ...

defrecord

(defrecord name [fields*] options* specs*) Options are expressed as sequential keywords and arguments (in any order)...

defstruct

Same as (def name (create-struct keys...))

deftype

(deftype name [fields*] options* specs*) Options are expressed as sequential keywords and arguments (in any order). ...

delay

Takes a body of expressions and yields a Delay object that will invoke the body only the first time it is forced (with...

delay?

returns true if x is a Delay created with delay

deliver

Delivers the supplied value to the promise, releasing any pending derefs. A subsequent call to deliver on a promise wi...

denominator

Returns the denominator part of a Ratio.

deref

Also reader macro: @ref/@agent/@var/@atom/@delay/@future/@promise. Within a transaction, returns the in-transaction-va...

derive

Establishes a parent/child relationship between parent and tag. Parent must be a namespace-qualified symbol or keyword...

descendants

Returns the immediate and indirect children of tag, through a relationship established via derive. h must be a hierarc...

destructure

disj

disj[oin]. Returns a new set of the same (hashed/sorted) type, that does not contain key(s).

disj!

disj[oin]. Returns a transient set of the same (hashed/sorted) type, that does not contain key(s).

dissoc

dissoc[iate]. Returns a new map of the same (hashed/sorted) type, that does not contain a mapping for key(s).

dissoc!

Returns a transient map that doesn't contain a mapping for key(s).

distinct

Returns a lazy sequence of the elements of coll with duplicates removed. Returns a stateful transducer when no collect...

distinct?

Returns true if no two of the arguments are =

do

Evaluates expressions in order, returning the last.

doall

When lazy sequences are produced via functions that have side effects, any effects other than those needed to produce ...

dorun

When lazy sequences are produced via functions that have side effects, any effects other than those needed to produce ...

doseq

Repeatedly executes body (presumably for side-effects) with bindings and filtering as provided by "for". Does not ret...

dosync

Runs the exprs (in an implicit do) in a transaction that encompasses exprs and any nested calls. Starts a transaction...

dotimes

bindings => name n Repeatedly executes body (presumably for side-effects) with name bound to integers from 0 throug...

doto

Evaluates x then calls all of the methods and functions with the value of x supplied at the front of the given argumen...

double

Coerce to double

double-array

Creates an array of doubles

double?

Return true if x is a Double

doubles

Casts to double[]

drop

Returns a laziness-preserving sequence of all but the first n items in coll. Returns a stateful transducer when no col...

drop-last

Return a lazy sequence of all but the last n (default 1) items in coll

drop-while

Returns a lazy sequence of the items in coll starting from the first item for which (pred item) returns logical false....

EMPTY-NODE

eduction

Returns a reducible/iterable application of the transducers to the items in coll. Transducers are applied in order as ...

empty

Returns an empty collection of the same category as coll, or nil

empty?

Returns true if coll has no items. To check the emptiness of a seq, please use the idiom (seq x) rather than (not (emp...

ensure

Must be called in a transaction. Protects the ref from modification by other transactions. Returns the in-transaction...

ensure-reduced

If x is already reduced?, returns it, else returns (reduced x)

enumeration-seq

Returns a seq on a java.util.Enumeration

error-handler

Returns the error-handler of agent a, or nil if there is none. See set-error-handler!

error-mode

Returns the error-mode of agent a. See set-error-mode!

eval

Evaluates the form data structure (not text!) and returns the result.

even?

Returns true if n is even, throws an exception if n is not an integer

every-pred

Takes a set of predicates and returns a function f that returns true if all of its composing predicates return a logic...

every?

Returns true if (pred x) is logical true for every x in coll, else false.

ex-cause

Returns the cause of ex if ex is a Throwable. Otherwise returns nil.

ex-data

Returns exception data (a map) if ex is an IExceptionInfo. Otherwise returns nil.

ex-info

Create an instance of ExceptionInfo, a RuntimeException subclass that carries a map of additional data.

ex-message

Returns the message attached to ex if ex is a Throwable. Otherwise returns nil.

extend

Implementations of protocol methods can be provided using the extend construct: (extend AType AProtocol {:fo...

extend-protocol

Useful when you want to provide several implementations of the same protocol all at once. Takes a single protocol and ...

extend-type

A macro that expands into an extend call. Useful when you are supplying the definitions explicitly inline, extend-type...

extenders

Returns a collection of the types explicitly extending protocol

extends?

Returns true if atype extends protocol

false?

Returns true if x is the value false, false otherwise.

ffirst

Same as (first (first x))

file-seq

A tree seq on java.io.Files

filter

Returns a lazy sequence of the items in coll for which (pred item) returns logical true. pred must be free of side-eff...

filterv

Returns a vector of the items in coll for which (pred item) returns logical true. pred must be free of side-effects.

finally

Finally clause inside try, runs on exit.

find

Returns the map entry for key, or nil if key not present.

find-keyword

Returns a Keyword with the given namespace and name if one already exists. This function will not intern a new keywor...

find-ns

Returns the namespace named by the symbol or nil if it doesn't exist.

find-protocol-impl

find-protocol-method

find-var

Returns the global var named by the namespace-qualified symbol, or nil if no var with that name.

first

Returns the first item in the collection. Calls seq on its argument. If coll is nil, returns nil.

flatten

Takes any nested combination of sequential things (lists, vectors, etc.) and returns their contents as a single, flat ...

float

Coerce to float

float-array

Creates an array of floats

float?

Returns true if n is a floating point number

floats

Casts to float[]

flush

Flushes the output stream that is the current value of *out*

fn

params => positional-params*, or positional-params* & rest-param positional-param => binding-form rest-param => bind...

fn?

Returns true if x implements Fn, i.e. is an object created via fn.

fnext

Same as (first (next x))

fnil

Takes a function f, and returns a function that calls f, replacing a nil first argument to f with the supplied value x...

for

List comprehension. Takes a vector of one or more binding-form/collection-expr pairs, each followed by zero or more ...

force

If x is a Delay, returns the (possibly cached) value of its expression, else returns x

format

Formats a string using java.lang.String.format, see java.util.Formatter for format string syntax

frequencies

Returns a map from distinct items in coll to the number of times they appear.

future

Takes a body of expressions and yields a future object that will invoke the body in another thread, and will cache the...

future-call

Takes a function of no args and yields a future object that will invoke the function in another thread, and will cache...

future-cancel

Cancels the future, if possible.

future-cancelled?

Returns true if future f is cancelled

future-done?

Returns true if future f is done

future?

Returns true if x is a future

gen-class

When compiling, generates compiled bytecode for a class with the given package-qualified :name (which, as all names in...

gen-interface

When compiling, generates compiled bytecode for an interface with the given package-qualified :name (which, as all nam...

gensym

Returns a new symbol with a unique name. If a prefix string is supplied, the name is prefix# where # is some unique nu...

get

Returns the value mapped to key, not-found or nil if key not present in associative collection, set, string, array, or...

get-in

Returns the value in a nested associative structure, where ks is a sequence of keys. Returns nil if the key is not p...

get-method

Given a multimethod and a dispatch value, returns the dispatch fn that would apply to that value, or nil if none apply...

get-proxy-class

Takes an optional single class followed by zero or more interfaces. If not supplied class defaults to Object. Creates...

get-thread-bindings

Get a map with the Var/value pairs which is currently in effect for the current thread.

get-validator

Gets the validator-fn for a var/ref/agent/atom.

group-by

Returns a map of the elements of coll keyed by the result of f on each element. The value at each key will be a vector...

halt-when

Returns a transducer that ends transduction when pred returns true for an input. When retf is supplied it must be a fn...

hash

Returns the hash code of its argument. Note this is the hash code consistent with =, and thus is different than .hashC...

hash-combine

hash-map

keyval => key val Returns a new hash map with supplied mappings. If any keys are equal, they are handled as if by r...

hash-ordered-coll

Returns the hash code, consistent with =, for an external ordered collection implementing Iterable. See http://clo...

hash-set

Returns a new hash set with supplied keys. Any equal keys are handled as if by repeated uses of conj.

hash-unordered-coll

Returns the hash code, consistent with =, for an external unordered collection implementing Iterable. For maps, the i...

Inst

ident?

Return true if x is a symbol or keyword

identical?

Tests if 2 arguments are the same object

identity

Returns its argument.

if

Evaluates test, then consequent or alternative.

if-let

bindings => binding-form test If test is true, evaluates then with binding-form bound to the value of test, if not...

if-not

Evaluates test. If logical false, evaluates and returns then expr, otherwise else expr, if supplied, else nil.

if-some

bindings => binding-form test If test is not nil, evaluates then with binding-form bound to the value of test, if...

ifn?

Returns true if x implements IFn. Note that many data structures (e.g. sets and maps) implement IFn

import

import-list => (package-symbol class-name-symbols*) For each name in class-name-symbols, adds a mapping from name to ...

in-ns

Sets *ns* to the namespace named by the symbol, creating it if needed.

inc

Returns a number one greater than num. Does not auto-promote longs, will throw on overflow. See also: inc'

inc'

Returns a number one greater than num. Supports arbitrary precision. See also: inc

indexed?

Return true if coll implements Indexed, indicating efficient lookup by index

infinite?

Returns true if num is negative or positive infinity, else false

init-proxy

Takes a proxy instance and a map of strings (which must correspond to methods of the proxy superclass/superinterfaces)...

inst-ms

Return the number of milliseconds since January 1, 1970, 00:00:00 GMT

inst-ms*

inst?

Return true if x satisfies Inst

instance?

Evaluates x and tests if it is an instance of the class c. Returns true or false

int

Coerce to int

int-array

Creates an array of ints

int?

Return true if x is a fixed precision integer

integer?

Returns true if n is an integer

interleave

Returns a lazy seq of the first item in each coll, then the second etc.

intern

Finds or creates a var named by the symbol name in the namespace ns (which can be a symbol or a namespace), setting it...

interpose

Returns a lazy seq of the elements of coll separated by sep. Returns a stateful transducer when no collection is provi...

into

Returns a new coll consisting of to with all of the items of from conjoined. A transducer may be supplied. (into x) ...

into-array

Returns an array with components set to the values in aseq. The array's component type is type if provided, or the typ...

ints

Casts to int[]

io!

If an io! block occurs in a transaction, throws an IllegalStateException, else runs body in an implicit do. If the f...

isa?

Returns true if (= child parent), or child is directly or indirectly derived from parent, either via a Java type inher...

iterate

Returns a lazy (infinite!) sequence of x, (f x), (f (f x)) etc. f must be free of side-effects

iteration

Creates a seqable/reducible via repeated calls to step, a function of some (continuation token) 'k'. The first call to...

iterator-seq

Returns a seq on a java.util.Iterator. Note that most collections providing iterators implement Iterable and thus supp...

juxt

Takes a set of functions and returns a fn that is the juxtaposition of those fns. The returned fn takes a variable nu...

keep

Returns a lazy sequence of the non-nil results of (f item). Note, this means false return values will be included. f ...

keep-indexed

Returns a lazy sequence of the non-nil results of (f index item). Note, this means false return values will be include...

key

Returns the key of the map entry.

keys

Returns a sequence of the map's keys, in the same order as (seq map).

keyword

Returns a Keyword with the given namespace and name. Do not use : in the keyword strings, it will be added automatica...

keyword?

Return true if x is a Keyword

last

Return the last item in coll, in linear time

lazy-cat

Expands to code which yields a lazy sequence of the concatenation of the supplied colls. Each coll expr is not evalua...

lazy-seq

Takes a body of expressions that returns an ISeq or nil, and yields a Seqable object that will invoke the body only th...

let

binding => binding-form init-expr binding-form => name, or destructuring-form destructuring-form => map-destructure-...

letfn

fnspec ==> (fname [params*] exprs) or (fname ([params*] exprs)+) Takes a vector of function specs and a body, and gen...

line-seq

Returns the lines of text from rdr as a lazy sequence of strings. rdr must implement java.io.BufferedReader.

list

Creates a new list containing the items.

list*

Creates a new seq containing the items prepended to the rest, the last of which will be treated as a sequence.

list?

Returns true if x implements IPersistentList

load

Loads Clojure code from resources in classpath. A path is interpreted as classpath-relative if it begins with a slash ...

load-file

Sequentially read and evaluate the set of forms contained in the file.

load-reader

Sequentially read and evaluate the set of forms contained in the stream/file

load-string

Sequentially read and evaluate the set of forms contained in the string

loaded-libs

Returns a sorted set of symbols naming the currently loaded libs

locking

Executes exprs in an implicit do, while holding the monitor of x. Will release the monitor of x in all circumstances.

long

Coerce to long

long-array

Creates an array of longs

longs

Casts to long[]

loop

Evaluates the exprs in a lexical context in which the symbols in the binding-forms are bound to their respective init-...

macroexpand

Repeatedly calls macroexpand-1 on form until it no longer represents a macro form, then returns it. Note neither ma...

macroexpand-1

If form represents a macro form, returns its expansion, else returns form.

make-array

Creates and returns an array of instances of the specified class of the specified dimension(s). Note that a class obj...

make-hierarchy

Creates a hierarchy object for use with derive, isa? etc.

map

Returns a lazy sequence consisting of the result of applying f to the set of first items of each coll, followed by app...

map-entry?

Return true if x is a map entry

map-indexed

Returns a lazy sequence consisting of the result of applying f to 0 and the first item of coll, followed by applying f...

map?

Return true if x implements IPersistentMap

mapcat

Returns the result of applying concat to the result of applying map to f and colls. Thus function f should return a c...

mapv

Returns a vector consisting of the result of applying f to the set of first items of each coll, followed by applying f...

max

Returns the greatest of the nums.

max-key

Returns the x for which (k x), a number, is greatest. If there are multiple such xs, the last one is returned.

memfn

Expands into code that creates a fn that expects to be passed an object and any args and calls the named instance meth...

memoize

Returns a memoized version of a referentially transparent function. The memoized version of the function keeps a cache...

merge

Returns a map that consists of the rest of the maps conj-ed onto the first. If a key occurs in more than one map, the...

merge-with

Returns a map that consists of the rest of the maps conj-ed onto the first. If a key occurs in more than one map, the...

meta

Returns the metadata of obj, returns nil if there is no metadata.

method-sig

methods

Given a multimethod, returns a map of dispatch values -> dispatch fns

min

Returns the least of the nums.

min-key

Returns the x for which (k x), a number, is least. If there are multiple such xs, the last one is returned.

mix-collection-hash

Mix final collection hash for ordered or unordered collections. hash-basis is the combined collection hash, count is ...

mod

Modulus of num and div. Truncates toward negative infinity.

monitor-enter

Acquires the monitor of an object.

monitor-exit

Releases the monitor of an object.

munge

NaN?

Returns true if num is NaN, else false

name

Returns the name String of a string, symbol or keyword.

namespace

Returns the namespace String of a symbol or keyword, or nil if not present.

namespace-munge

Convert a Clojure namespace name to a legal Java package name.

nat-int?

Return true if x is a non-negative fixed precision integer

neg-int?

Return true if x is a negative fixed precision integer

neg?

Returns true if num is less than zero, else false

new

Creates a new instance of a class.

newline

Writes a platform-specific newline to *out*

next

Returns a seq of the items after the first. Calls seq on its argument. If there are no more items, returns nil.

nfirst

Same as (next (first x))

nil?

Returns true if x is nil, false otherwise.

nnext

Same as (next (next x))

not

Returns true if x is logical false, false otherwise.

not-any?

Returns false if (pred x) is logical true for any x in coll, else true.

not-empty

If coll is empty, returns nil, else coll

not-every?

Returns false if (pred x) is logical true for every x in coll, else true.

not=

Same as (not (= obj1 obj2))

ns

Sets *ns* to the namespace named by name (unevaluated), creating it if needed. references can be zero or more of: (:r...

ns-aliases

Returns a map of the aliases for the namespace.

ns-imports

Returns a map of the import mappings for the namespace.

ns-interns

Returns a map of the intern mappings for the namespace.

ns-map

Returns a map of all the mappings for the namespace.

ns-name

Returns the name of the namespace, a symbol.

ns-publics

Returns a map of the public intern mappings for the namespace.

ns-refers

Returns a map of the refer mappings for the namespace.

ns-resolve

Returns the var or Class to which a symbol will be resolved in the namespace (unless found in the environment), else n...

ns-unalias

Removes the alias for the symbol from the namespace.

ns-unmap

Removes the mappings for the symbol from the namespace.

nth

Returns the value at the index. get returns nil if index out of bounds, nth throws an exception unless not-found is su...

nthnext

Returns the nth next of coll, (seq coll) when n is 0.

nthrest

Returns the nth rest of coll, coll when n is 0.

num

Coerce to Number

number?

Returns true if x is a Number

numerator

Returns the numerator part of a Ratio.

object-array

Creates an array of objects

odd?

Returns true if n is odd, throws an exception if n is not an integer

or

Evaluates exprs one at a time, from left to right. If a form returns a logical true value, or returns that value and d...

PrintWriter-on

implements java.io.PrintWriter given flush-fn, which will be called when .flush() is called, with a string built up si...

parents

Returns the immediate parents of tag, either via a Java type inheritance relationship or a relationship established vi...

parse-boolean

Parse strings "true" or "false" and return a boolean, or nil if invalid

parse-double

Parse string with floating point components and return a Double value, or nil if parse fails. Grammar: https://docs...

parse-long

Parse string of decimal digits with optional leading -/+ and return a Long value, or nil if parse fails

parse-uuid

Parse a string representing a UUID and return a java.util.UUID instance, or nil if parse fails. Grammar: https://do...

partial

Takes a function f and fewer than the normal arguments to f, and returns a fn that takes a variable number of addition...

partition

Returns a lazy sequence of lists of n items each, at offsets step apart. If step is not supplied, defaults to n, i.e. ...

partition-all

Returns a lazy sequence of lists like partition, but may include partitions with fewer than n items at the end. Retur...

partition-by

Applies f to each value in coll, splitting it each time f returns a new value. Returns a lazy seq of partitions. Re...

partitionv

Returns a lazy sequence of vectors of n items each, at offsets step apart. If step is not supplied, defaults to n, i.e...

partitionv-all

Returns a lazy sequence of vector partitions, but may include partitions with fewer than n items at the end. Returns...

pcalls

Executes the no-arg fns in parallel, returning a lazy sequence of their values

peek

For a list or queue, same as first, for a vector, same as, but much more efficient than, last. If the collection is em...

persistent!

Returns a new, persistent version of the transient collection, in constant time. The transient collection cannot be us...

pmap

Like map, except f is applied in parallel. Semi-lazy in that the parallel computation stays ahead of the consumption, ...

pop

For a list or queue, returns a new list/queue without the first item, for a vector, returns a new vector without the l...

pop!

Removes the last item from a transient vector. If the collection is empty, throws an exception. Returns coll

pop-thread-bindings

Pop one set of bindings pushed with push-binding before. It is an error to pop bindings without pushing before.

pos-int?

Return true if x is a positive fixed precision integer

pos?

Returns true if num is greater than zero, else false

pr

Prints the object(s) to the output stream that is the current value of *out*. Prints the object(s), separated by spac...

pr-str

pr to a string, returning it

prefer-method

Causes the multimethod to prefer matches of dispatch-val-x over dispatch-val-y when there is a conflict

prefers

Given a multimethod, returns a map of preferred value -> set of other values

primitives-classnames

print

Prints the object(s) to the output stream that is the current value of *out*. print and println produce output for hu...

print-ctor

print-dup

print-method

print-simple

print-str

print to a string, returning it

printf

Prints formatted output, as per format

println

Same as print followed by (newline)

println-str

println to a string, returning it

prn

Same as pr followed by (newline). Observes *flush-on-newline*

prn-str

prn to a string, returning it

promise

Returns a promise object that can be read with deref/@, and set, once only, with deliver. Calls to deref/@ prior to de...

proxy

class-and-interfaces - a vector of class names args - a (possibly empty) vector of arguments to the superclass cons...

proxy-call-with-super

proxy-mappings

Takes a proxy instance and returns the proxy's fn map.

proxy-name

proxy-super

Use to call a superclass method in the body of a proxy method. Note, expansion captures 'this

push-thread-bindings

WARNING: This is a low-level function. Prefer high-level macros like binding where ever possible. Takes a map of Va...

pvalues

Returns a lazy sequence of the values of the exprs, which are evaluated in parallel

qualified-ident?

Return true if x is a symbol or keyword with a namespace

qualified-keyword?

Return true if x is a keyword with a namespace

qualified-symbol?

Return true if x is a symbol with a namespace

quot

quot[ient] of dividing numerator by denominator.

quote

Yields the unevaluated form.

rand

Returns a random floating point number between 0 (inclusive) and n (default 1) (exclusive).

rand-int

Returns a random integer between 0 (inclusive) and n (exclusive).

rand-nth

Return a random element of the (sequential) collection. Will have the same performance characteristics as nth for the ...

random-sample

Returns items from coll with random probability of prob (0.0 - 1.0). Returns a transducer when no collection is provi...

random-uuid

Returns a pseudo-randomly generated java.util.UUID instance (i.e. type 4). See: https://docs.oracle.com/javase/8/docs...

range

Returns a lazy seq of nums from start (inclusive) to end (exclusive), by step, where start defaults to 0, step to 1, a...

ratio?

Returns true if n is a Ratio

rational?

Returns true if n is a rational number

rationalize

returns the rational value of num

re-find

Returns the next regex match, if any, of string to pattern, using java.util.regex.Matcher.find(). Uses re-groups to r...

re-groups

Returns the groups from the most recent match/find. If there are no nested groups, returns a string of the entire matc...

re-matcher

Returns an instance of java.util.regex.Matcher, for use, e.g. in re-find.

re-matches

Returns the match, if any, of string to pattern, using java.util.regex.Matcher.matches(). Uses re-groups to return th...

re-pattern

Returns an instance of java.util.regex.Pattern, for use, e.g. in re-matcher.

re-seq

Returns a lazy sequence of successive matches of pattern in string, using java.util.regex.Matcher.find(), each such ma...

read

Reads the next object from stream, which must be an instance of java.io.PushbackReader or some derivee. stream defaul...

read+string

Like read, and taking the same args. stream must be a LineNumberingPushbackReader. Returns a vector containing the obj...

read-line

Reads the next line from stream that is the current value of *in* .

read-string

Reads one object from the string s. Optionally include reader options, as specified in read. Note that read-string ...

reader-conditional

Construct a data representation of a reader conditional. If true, splicing? indicates read-cond-splicing.

reader-conditional?

Return true if the value is the data representation of a reader conditional

realized?

Returns true if a value has been produced for a promise, delay, future or lazy sequence.

record?

Returns true if x is a record

recur

Rebinds and transfers control to the recursion point.

reduce

f should be a function of 2 arguments. If val is not supplied, returns the result of applying f to the first 2 items i...

reduce-kv

Reduces an associative collection. f should be a function of 3 arguments. Returns the result of applying f to init, th...

reduced

Wraps x in a way such that a reduce will terminate with the value x

reduced?

Returns true if x is the result of a call to reduced

reductions

Returns a lazy seq of the intermediate values of the reduction (as per reduce) of coll by f, starting with init.

ref

Creates and returns a Ref with an initial value of x and zero or more options (in any order): :meta metadata-map ...

ref-history-count

Returns the history count of a ref

ref-max-history

Gets the max-history of a ref, or sets it and returns the ref

ref-min-history

Gets the min-history of a ref, or sets it and returns the ref

ref-set

Must be called in a transaction. Sets the value of ref. Returns val.

refer

refers to all public vars of ns, subject to filters. filters can include at most one each of: :exclude list-of-symb...

refer-clojure

Same as (refer 'clojure.core <filters>)

reify

reify creates an object implementing a protocol or interface. reify is a macro with the following structure: (reify ...

release-pending-sends

Normally, actions sent directly or indirectly during another action are held until the action completes (changes the a...

rem

remainder of dividing numerator by denominator.

remove

Returns a lazy sequence of the items in coll for which (pred item) returns logical false. pred must be free of side-ef...

remove-all-methods

Removes all of the methods of multimethod.

remove-method

Removes the method of multimethod associated with dispatch-value.

remove-ns

Removes the namespace named by the symbol. Use with caution. Cannot be used to remove the clojure namespace.

remove-tap

Remove f from the tap set.

remove-watch

Removes a watch (set by add-watch) from a reference

repeat

Returns a lazy (infinite!, or length n if supplied) sequence of xs.

repeatedly

Takes a function of no args, presumably with side effects, and returns an infinite (or length n if supplied) lazy sequ...

replace

Given a map of replacement pairs and a vector/collection, returns a vector/seq with any elements = a key in smap repla...

require

Loads libs, skipping any that are already loaded. Each argument is either a libspec that identifies a lib, a prefix li...

requiring-resolve

Resolves namespace-qualified sym per 'resolve'. If initial resolve fails, attempts to require sym's namespace and retrie...

reset!

Sets the value of atom to newval without regard for the current value. Returns newval.

reset-meta!

Atomically resets the metadata for a namespace/var/ref/agent/atom

reset-vals!

Sets the value of atom to newval. Returns [old new], the value of the atom before and after the reset.

resolve

same as (ns-resolve *ns* symbol) or (ns-resolve *ns* &env symbol)

rest

Returns a possibly empty seq of the items after the first. Calls seq on its argument.

restart-agent

When an agent is failed, changes the agent state to new-state and then un-fails the agent so that sends are allowed ag...

resultset-seq

Creates and returns a lazy sequence of structmaps corresponding to the rows in the java.sql.ResultSet rs

reverse

Returns a seq of the items in coll in reverse order. Not lazy.

reversible?

Returns true if coll implements Reversible

rseq

Returns, in constant time, a seq of the items in rev (which can be a vector or sorted-map), in reverse order. If rev i...

rsubseq

sc must be a sorted collection, test(s) one of <, <=, > or >=. Returns a reverse seq of those entries with keys ek for...

run!

Runs the supplied procedure (via reduce), for purposes of side effects, on successive items in the collection. Returns...

StackTraceElement->vec

Constructs a data representation for a StackTraceElement: [class method file line]

satisfies?

Returns true if x satisfies the protocol

second

Same as (first (next x))

select-keys

Returns a map containing only those entries in map whose key is in keys

send

Dispatch an action to an agent. Returns the agent immediately. Subsequently, in a thread from a thread pool, the state...

send-off

Dispatch a potentially blocking action to an agent. Returns the agent immediately. Subsequently, in a separate thread,...

send-via

Dispatch an action to an agent. Returns the agent immediately. Subsequently, in a thread supplied by executor, the sta...

seq

Returns a seq on the collection. If the collection is empty, returns nil. (seq nil) returns nil. seq also works on ...

seq-to-map-for-destructuring

Builds a map from a seq as described in https://clojure.org/reference/special_forms#keyword-arguments

seq?

Return true if x implements ISeq

seqable?

Return true if the seq function is supported for x

seque

Creates a queued seq on another (presumably lazy) seq s. The queued seq will produce a concrete seq in the background,...

sequence

Coerces coll to a (possibly empty) sequence, if it is not already one. Will not force a lazy seq. (sequence nil) yield...

sequential?

Returns true if coll implements Sequential

set

Returns a set of the distinct elements of coll.

set!

Assigns a new value to a var or field.

set-agent-send-executor!

Sets the ExecutorService to be used by send

set-agent-send-off-executor!

Sets the ExecutorService to be used by send-off

set-error-handler!

Sets the error-handler of agent a to handler-fn. If an action being run by the agent throws an exception or doesn't p...

set-error-mode!