Community documentation for Janet

(find |(= 2 $) {:a 1 :b 2 :c 3})
# => 2

(get @"Hello" 1)
# => 101

(find |(= 101 $)  @"Hello")
# => 101

(find |(> $ 3)  {:a 1 :b 2 :c 3})
# => nil

(def a @[1 6])                     # => @[1 6]
(array/insert a 1 (splice [2 3]))  # => @[1 2 3 6]
(array/insert a 3 ;[4 5])          # => @[1 2 3 4 5 6]

#!/usr/bin/env janet
# echo stdin to stdout.
(file/write stdout (file/read stdin :all))

(string/format "%f" (os/clock)) # => "1627746483.991000"

(any? "")
# => nil

(any? "Hello")
# => 72

(any? @"Hello")
# => 72

(any? @[])
# => nil

(any? [])
# => nil

(any? {})
# => nil

(any? @{})
# => nil

(any? @[1 2 3 4])
# => 1 

(any? @{:a 2 :b 3})
# => 2

(map math/abs   [-2.9 -2.1 2.1 2.9])  # => @[ 2.9  2.1  2.1  2.9 ]
(map math/floor [-2.9 -2.1 2.1 2.9])  # => @[ -3   -3   2    2   ]
(map math/ceil  [-2.9 -2.1 2.1 2.9])  # => @[ -2   -2   3    3   ]
(map math/round [-2.9 -2.1 2.1 2.9])  # => @[ -3   -2   2    3   ]
(map math/trunc [-2.9 -2.1 2.1 2.9])  # => @[ -2   -2   2    2   ]

(for i 0 5 
     (print i))
 
# 0
# 1
# 2
# 3
# 4

# => nil

(let [tbl @{:a 1}]
  (merge-into tbl {:b 2})
  tbl)
# => @{:a 1 :b 2}

# real-world example: https://git.sr.ht/~subsetpark/bagatto/tree/19aea03fe23fe5486890912df7dc4a936ce617a3/item/main.janet#L23

(cmp 0.0 0)
# => 0

(some odd? [2 4 6 8 10])
# =>
nil

# note that 'not' works as an implementation of 'falsey?'
(map not     [ nil   false true  0     1     'a    :a    "a"   []    {}    (fn []) ])
# =>        @[ true  true  false false false false false false false false false   ]

(map truthy? [ nil   false true  0     1     'a    :a    "a"   []    {}    (fn []) ])
# =>        @[ false false true  true  true  true  true  true  true  true  true    ]

(drop-until |(> $ 8)
            [1 1 2 3 4 5 8 13 21])
# => '(13 21)

(inc 42)  # => 43
(map inc [1 2 3])  # => @[2 3 4]

(keyword/slice "some crazy keyword" 11 -1)
# returns :keyword 

(map dictionary? [ 'ab   :ab   "ab"   @"ab"  [97 98]  @[97 98]  {0 97 1 98}  @{0 97 1 98}  ])
# =>            @[ false false false  false  false    false     true         true          ]

(map struct?     [ 'ab   :ab   "ab"   @"ab"  [97 98]  @[97 98]  {0 97 1 98}  @{0 97 1 98}  ])
# =>            @[ false false false  false  false    false     true         false         ]

(map table?      [ 'ab   :ab   "ab"   @"ab"  [97 98]  @[97 98]  {0 97 1 98}  @{0 97 1 98}  ])
# =>            @[ false false false  false  false    false     false        true          ]