Clojure Core Essentials

YS has a very large set of useful functions that it inherits from Clojure's clojure.core library ⧉.

These functions are the bread and butter building blocks of YS programming.

The functions are very well organized in the Clojure Docs Quick Reference ⧉ and you can get to the documentation for each function from there.

This document is a condensed quick reference of the functions that are most commonly used in YS programming.

YS also has the ys::std standard library that provides additional functions.

The YS standard library replaces some Clojure functions with a version more suited to YS. In those cases, the original Clojure function is still available in the ys::clj namespace.

Number

Arithmetic

Clojure Core:

• + ⧉, - ⧉, * ⧉, / ⧉, inc ⧉, dec ⧉, max ⧉, min ⧉, rand ⧉, rand-int ⧉

YS Std:

• %, %% infix operators
• add, sub, mul, div named math functions
• sum, sqr, cube, sqrt, pow, abs
• add+, sub+, mul+, div+ polymorphic functions

See Also:

• clojure.math ⧉ functions callable as math/<func-name> in YS.

Comparison

Clojure Core:

• < ⧉, > ⧉, <= ⧉, >= ⧉

YS Std:

• ==, != infix operators
• eq, ne, lt, gt, le, ge named comparison functions

Cast

Clojure Core:

• byte ⧉, short ⧉, int ⧉, long ⧉, float ⧉, double ⧉, num ⧉

YS Std:

• to-num, to-int, to-float - polymorphic cast functions

Test

Clojure Core:

• zero? ⧉, pos? ⧉, neg? ⧉, even? ⧉, odd? ⧉, number? ⧉

Boolean

Clojure Core:

• nil? ⧉, true? ⧉, false? ⧉, boolean ⧉

YS Std:

• truey?, falsey?, to-bool, to-booly

String

Clojure Core:

• str ⧉, pr-str ⧉, prn-str ⧉, with-out-str ⧉, count ⧉, subs ⧉, format ⧉, string? ⧉

YS Std:

• words, split, join, lines, text, replace, replace1
• chomp, trim, triml, trimr, lc, uc, uc1, index, pretty

See Also:

• clojure.string ⧉ functions callable as str/<func-name> in YS.

Regular Expression

Clojure Core:

• re-pattern ⧉, re-matches ⧉, re-find ⧉, re-seq ⧉, re-groups ⧉

YS Std:

• =~, !~ infix operators
• /.../ regex literals
• qr

Flow Control

Boolean

Clojure Core:

• not ⧉, and ⧉, or ⧉

YS Std:

• ||, &&, |||, &&& infix operators
• or?, and? booly named functions

Normal

Clojure Core:

• if ⧉, when ⧉, if-not ⧉, when-not ⧉, if-let ⧉, when-let ⧉, if-some ⧉, when-some ⧉, cond ⧉, condp ⧉, case ⧉, do ⧉, eval ⧉, loop ⧉, recur ⧉, while ⧉

YS Std:

• if-lets, when-lets, call, each, exit, sleep

Exception

Clojure Core:

• try ⧉, catch ⧉, finally ⧉, throw ⧉, assert ⧉

YS Std:

• die, warn, exit, err

Function

Clojure Core:

• fn ⧉, defn ⧉, defn- ⧉, identity ⧉, comp ⧉, partial ⧉, complement ⧉, constantly ⧉, -> ⧉, ->> ⧉, apply ⧉, fn? ⧉, ifn? ⧉

YS Std:

• \(...) anonymous function syntax
• . dot chaining infix operator
• value, call

Collection

General

Clojure Core:

• count ⧉, empty ⧉, not-empty ⧉, into ⧉, conj ⧉, contains? ⧉, distinct? ⧉, empty? ⧉, every? ⧉, some ⧉, not-every? ⧉, not-any? ⧉, coll? ⧉, seq? ⧉, vector? ⧉, list? ⧉, map? ⧉, set? ⧉, sorted? ⧉, sequential? ⧉, associative? ⧉

YS Std:

• grep, has?, in?

Vector

Clojure Core:

• vec ⧉, vector ⧉, vec-of ⧉, conj ⧉, peek ⧉, pop ⧉, get ⧉

List

Clojure Core:

• list ⧉, cons ⧉, conj ⧉, peek ⧉, pop ⧉, first ⧉, rest ⧉

Map

Clojure Core:

• hash-map ⧉, array-map ⧉, sorted-map ⧉, zipmap ⧉, frequencies ⧉, assoc ⧉, assoc-in ⧉, dissoc ⧉, find ⧉, get-in ⧉, update-in ⧉, key ⧉, val ⧉, keys ⧉, vals ⧉, merge ⧉, reduce-kv ⧉

YS Std:

• omap, get+

Sequence

Clojure Core:

• seq ⧉, repeat ⧉, range ⧉, iterate ⧉, cycle ⧉, interleave ⧉, interpose ⧉, first ⧉, second ⧉, last ⧉, rest ⧉, next ⧉, butlast ⧉, nth ⧉, take ⧉, drop ⧉, take-while ⧉, drop-while ⧉, conj ⧉, concat ⧉, map ⧉, filter ⧉, remove ⧉, sort ⧉, shuffle ⧉, flatten ⧉, for ⧉, doseq ⧉, dorun ⧉, doall ⧉, mapcat ⧉, reduce ⧉, keep ⧉

YS Std:

• .. infix rng operator
• rng, reverse

Variable

Clojure Core:

• def ⧉, intern ⧉, declare ⧉, binding ⧉, gensym ⧉, var ⧉, var-get ⧉, resolve ⧉, find-var ⧉, alter-var-root ⧉, var? ⧉, bound? ⧉

YS Std:

• =:, .=:, +=:, -=:, *=:, /=: def/let syntax
• value

I/O

Clojure Core:

• print ⧉, printf ⧉, println ⧉, pr ⧉, prn ⧉, print-str ⧉, println-str ⧉, pr-str ⧉, prn-str ⧉, newline ⧉, flush ⧉, slurp ⧉, spit ⧉, with-out-str ⧉, with-open ⧉, with-in-str ⧉

YS Std:

• say, out, warn, pp