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  , read  , write  , with-out-str  , with-open  , with-in-str 

YS Std:

• say, out, warn, pp