Collections

count

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

empty

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

find

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

find

Return `zloc` located to the first node satisfying predicate `p?` else nil. Search starts at the current node and con...

first

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

get

get

Convenience wrapper for `request` with method `:get`

get

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

get

Issues an async HTTP GET request. See `request` for details.

get

Returns `zloc` located to map key node's sexpr value matching `k` else `nil`. `k` should be: - a key for maps - a...

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...

key

Returns the key of the map entry.

keys

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

last

Return the last item in coll, in linear time

next

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

next

Moves to the next loc in the hierarchy, depth-first. When reaching the end, returns a distinguished loc detectable via...

next

Return zipper with location moved to the next depth-first non-whitespace/non-comment node in `zloc`. End can be detec...

nth

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

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...

rest

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

second

Same as (first (next x))

seq

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

seq

Create a lazy-seq of all of the (unique) nodes in a shrink-tree. This assumes that two nodes with the same value have ...

sequence

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

val

Returns the value in the map entry.

vals

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

array-map

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

cycle

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

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-map

Like clojure.core/hash-map, except the values are generators. Returns a generator that makes maps with the supplied k...

hash-set

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

iterate

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

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...

list

Creates a new list containing the items.

list

Like `vector`, but generates lists.

list*

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

range

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

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...

set

Returns a set of the distinct elements of coll.

set

Generates a set of elements from the given generator. If the generator cannot or is unlikely to produce enough distin...

sorted-map

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

sorted-map-by

keyval => key val Returns a new sorted map with supplied mappings, using the supplied comparator. If any keys are e...

sorted-set

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

sorted-set

Generates a sorted set of elements from the given generator. If the generator cannot or is unlikely to produce enough...

sorted-set-by

Returns a new sorted set with supplied keys, using the supplied comparator. Any equal keys are handled as if by repea...

vec

Creates a new vector containing the contents of coll. Java arrays will be aliased and should not be modified.

vector

Creates a new vector containing the args.

vector

Creates a generator of vectors whose elements are chosen from `generator`. The count of the vector will be bounded by ...

zipmap

Returns a map with the keys mapped to the corresponding vals.

assoc

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

assoc

Returns `zloc` with current node's `k` set to value `v`. `zloc` location is unchanged. `k` should be: - a key fo...

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...

conj

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

cons

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

disj

disj[oin]. Returns a new 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).

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...

update

'Updates' a value in an associative structure, where k is a key and f is a function that will take the old value and...

update-in

'Updates' a value in a nested associative structure, where ks is a sequence of keys and f is a function that will take...

associative?

Returns true if coll implements Associative

chunked-seq?

coll?

Returns true if x implements IPersistentCollection

contains?

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

counted?

Returns true if coll implements count in constant time

distinct?

Returns true if no two of the arguments are =

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...

every?

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

indexed?

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

list?

Returns true if x implements IPersistentList

list?

Returns true if current node in `zloc` is a list.

map-entry?

Return true if x is a map entry

map?

Return true if x implements IPersistentMap

map?

Returns true if current node in `zloc` is a map.

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-empty

Modifies a generator so that it doesn't generate empty collections. Examples: ;; generate a vector of booleans...

not-every?

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

record?

Returns true if x is a record

reversible?

Returns true if coll implements Reversible

seq?

Return true if x implements ISeq

seq?

Returns true if current node in `zloc` is a sequence.

seqable?

Return true if the seq function is supported for x

sequential?

Returns true if coll implements Sequential

set?

Returns true if x implements IPersistentSet

set?

Returns true if current node in `zloc` is a set.

some

Returns the first logical true value of (pred x) for any x in coll, else nil. One common idiom is to use a set as pre...

sorted?

Returns true if coll implements Sorted

vector?

Return true if x implements IPersistentVector

vector?

Returns true if current node in `zloc` is a vector.

difference

Return a set that is the first set without elements of the remaining sets

index

Returns a map of the distinct values of ks in the xrel mapped to a set of the maps in xrel with the corresponding valu...

intersection

Return a set that is the intersection of the input sets

join

When passed 2 rels, returns the rel corresponding to the natural join. When passed an additional keymap, joins on the ...

map-invert

Returns the map with the vals mapped to the keys.

project

Returns a rel of the elements of xrel with only the keys in ks

rename

Returns a rel of the maps in xrel with the keys in kmap renamed to the vals in kmap

rename-keys

Returns the map with the keys in kmap renamed to the vals in kmap

select

Returns a set of the elements for which pred is true

subset?

Is set1 a subset of set2?

superset?

Is set1 a superset of set2?

union

Return a set that is the union of the input sets

butlast

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

cat

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

concat

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

dedupe

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

distinct

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

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...

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....

eduction

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

filter

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

filter

Returns a new Rose tree whose values pass `pred`. Values who do not pass `pred` have their children cut out as well.

filterv

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

flatten

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

for

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

frequencies

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

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...

interleave

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

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

Returns a channel containing the single (collection) result of the items taken from the channel conjoined to the suppl...

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...

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

Takes a function and a collection of source channels, and returns a channel which contains the values produced by appl...

map

Creates a generator that generates maps, with keys chosen from `key-gen` and values chosen from `val-gen`. If the k...

map

Returns `zloc` with function `f` applied to all nodes of the current node. Current node must be a sequence node. Equiv...

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...

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...

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

Takes a collection of source channels and returns a channel which contains all values taken from them. The returned ch...

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...

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.

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

Deprecated - this function will be removed. Use transducer instead

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...

partition-by

Deprecated - this function will be removed. Use transducer instead

random-sample

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

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

f should be a function of 2 arguments. Returns a channel containing the single result of applying f to init and the fi...

reduce-kv

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

reductions

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

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

remove

Removes the node at loc, returning the loc that would have preceded it in a depth-first walk.

remove

Return `zloc` with current node removed. Returned zipper location is moved to the first non-whitespace node preceding...

replace

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

replace

Replaces all instance of match with replacement in s. match/replacement can be: string / string char / char ...

replace

Replaces the node at this loc, without moving

replace

Return `zloc` with the current node replaced by `item`. If `item` is not already a node, an attempt will be made to co...

reverse

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

reverse

Returns s with its characters reversed.

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...

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...

select-keys

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

shuffle

Return a random permutation of coll

shuffle

Creates a generator that generates random permutations of `coll`. Shrinks toward the original collection: `coll`. `col...

sort

Returns a sorted sequence of the items in coll. If no comparator is supplied, uses compare. comparator must implement...

sort-by

Returns a sorted sequence of the items in coll, where the sort order is determined by comparing (keyfn item). If no c...

split-at

Returns a vector of [(take n coll) (drop n coll)]

split-with

Returns a vector of [(take-while pred coll) (drop-while pred coll)]

subseq

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

subseq

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

take

Returns a lazy sequence of the first n items in coll, or all items if there are fewer than n. Returns a stateful tran...

take

Returns a channel that will return, at most, n items from ch. After n items have been returned, or ch has been closed...

take-last

Returns a seq of the last n items in coll. Depending on the type of coll may be no better than linear time. For vect...

take-nth

Returns a lazy seq of every nth item in coll. Returns a stateful transducer when no collection is provided.

take-while

Returns a lazy sequence of successive items from coll while (pred item) returns logical true. pred must be free of sid...

transduce

reduce with a transformation of f (xf). If init is not supplied, (f) will be called to produce it. f should be a reduc...

transduce

async/reduces a channel with a transformation (xform f). Returns a channel containing the result. ch must close befor...

tree-seq

Returns a lazy sequence of the nodes in a tree, via a depth-first walk. branch? must be a fn of one arg that returns ...

update-keys

m f => {(f k) v ...} Given a map m and a function f of 1-argument, returns a new map whose keys are the result of a...

update-vals

m f => {k (f v) ...} Given a map m and a function f of 1-argument, returns a new map where the keys of m are mapped...

xml-seq

A tree seq on the xml elements as per xml/parse

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...

conj!

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

disj!

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

dissoc!

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

persistent!

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

pop!

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

transient

Returns a new, transient version of the collection, in constant time. Transients support a parallel set of 'changing'...