Data: math, strings, arrays, objects

Every operator a .lolo program can call, from the canonical registry the compiler bakes.

On this page

Namespaces on this page: array/, data/, json/, math/, object/, path/, str/.

array/

`array/append`

Add item to end (returns new array)

lolo

(array/append arr item)

Parameters

Name	Type	Description
`arr`	`array`	The array
`item`	`any`	Item to add

Returns: array

Example

lolo

(array/append [1 2] 3) // => [1, 2, 3]

`array/avg`

Average of values (optionally by field)

lolo

(array/avg arr key)

Parameters

Name	Type	Description
`arr`	`array`	The array
`key`	`string`	Field to average

Returns: number

Example

lolo

(array/avg [{"score":80},{"score":90}] "score")

`array/concat`

Concatenate arrays

lolo

(array/concat ...arrs)

Parameters

Name	Type	Description
`...arrs`	`array[]`	Arrays to concatenate

Returns: array

Example

lolo

(array/concat [1 2] [3 4]) // => [1, 2, 3, 4]

`array/cosine`

Cosine similarity between two numeric vectors, in [-1, 1] (1 = identical direction). The building block for "is this answer semantically the reference answer" checks over embeddings. Pure math — usable in guards and value position, unlike the async llm/* substrate operators.

lolo

(array/cosine v1 v2)

Parameters

Name	Type	Description
`v1`	`array`	First numeric vector
`v2`	`array`	Second numeric vector

Returns: number

Example

lolo

(array/cosine [1 0] [1 0]) // => 1

`array/count`

Count elements (optionally matching predicate)

lolo

(array/count arr pred)

Parameters

Name	Type	Description
`arr`	`array`	The array
`pred`	`lambda`	Predicate function

Returns: number

Example

lolo

(array/count [{"status":"done"},{"status":"todo"}] ["fn","t",["=","@t.status","done"]])

`array/drop`

Skip first n elements

lolo

(array/drop arr n)

Parameters

Name	Type	Description
`arr`	`array`	The array
`n`	`number`	Number of elements to skip

Returns: array

Example

lolo

(array/drop [1,2,3,4,5,6,7] 5)

`array/dropLast`

Skip last n elements

lolo

(array/dropLast arr n)

Parameters

Name	Type	Description
`arr`	`array`	The array
`n`	`number`	Number of elements to skip

Returns: array

Example

lolo

(array/dropLast [1,2,3,4,5] 2)

`array/every`

Check if all elements match predicate

lolo

(array/every arr pred)

Parameters

Name	Type	Description
`arr`	`array`	The array
`pred`	`lambda`	Predicate function

Returns: boolean

Example

lolo

(array/every [{"price":5},{"price":10}] ["fn","x",[">","@x.price",0]])

`array/filter`

Keep elements matching predicate (returns same array element type as input)

lolo

(array/filter arr pred)

Parameters

Name	Type	Description
`arr`	`array`	The array
`pred`	`lambda`	Predicate function

Returns: array

Example

lolo

(array/filter [{"price":50},{"price":150}] ["fn","x",[">","@x.price",100]])

`array/find`

Find first element matching predicate (element type of input array, undefined when no match)

lolo

(array/find arr pred)

Parameters

Name	Type	Description
`arr`	`array`	The array
`pred`	`lambda`	Predicate function

Returns: any

Example

lolo

(array/find [{"status":"active"},{"status":"archived"}] ["fn","x",["=","@x.status","active"]])

`array/findIndex`

Find index of first element matching predicate (-1 if none)

lolo

(array/findIndex arr pred)

Parameters

Name	Type	Description
`arr`	`array`	The array
`pred`	`lambda`	Predicate function

Returns: number

Example

lolo

(array/findIndex [{"status":"active"},{"status":"archived"}] ["fn","x",["=","@x.status","active"]])

`array/first`

Get first element (element type of input array, may be undefined when empty)

lolo

(array/first arr)

Parameters

Name	Type	Description
`arr`	`array`	The array

Returns: any

Example

lolo

(array/first [1 2 3]) // => 1

`array/flatten`

Flatten nested arrays one level

lolo

(array/flatten arr)

Parameters

Name	Type	Description
`arr`	`array`	The array

Returns: array

Example

lolo

(array/flatten [[1 2] [3 4]]) // => [1, 2, 3, 4]

`array/groupBy`

Group elements by field value

lolo

(array/groupBy arr key)

Parameters

Name	Type	Description
`arr`	`array`	The array
`key`	`string`	Field to group by

Returns: any

Example

lolo

(array/groupBy [{"status":"new"},{"status":"done"}] "status")

`array/includes`

Check if array contains item

lolo

(array/includes arr item)

Parameters

Name	Type	Description
`arr`	`array`	The array
`item`	`any`	Item to find

Returns: boolean

Example

lolo

(array/includes [1 2 3] 2) // => true

`array/indexOf`

Find index of item (-1 if not found)

lolo

(array/indexOf arr item)

Parameters

Name	Type	Description
`arr`	`array`	The array
`item`	`any`	Item to find

Returns: number

Example

lolo

(array/indexOf [1 2 3] 2) // => 1

`array/insert`

Insert item at index (returns new array)

lolo

(array/insert arr index item)

Parameters

Name	Type	Description
`arr`	`array`	The array
`index`	`number`	Index to insert at
`item`	`any`	Item to insert

Returns: array

Example

lolo

(array/insert [1 3] 1 2) // => [1, 2, 3]

`array/last`

Get last element (element type of input array, may be undefined when empty)

lolo

(array/last arr)

Parameters

Name	Type	Description
`arr`	`array`	The array

Returns: any

Example

lolo

(array/last [1 2 3]) // => 3

`array/len`

Array length

lolo

(array/len arr)

Parameters

Name	Type	Description
`arr`	`array`	The array

Returns: number

Example

lolo

(array/len [1 2 3]) // => 3

`array/map`

Transform each element (return type wraps the lambda result in an array)

lolo

(array/map arr fn)

Parameters

Name	Type	Description
`arr`	`array`	The array
`fn`	`lambda`	Transform function

Returns: array

Example

lolo

(array/map [{"price":100},{"price":200}] ["fn","x",["*","@x.price",1.1]])

`array/max`

Maximum value (optionally by field)

lolo

(array/max arr key)

Parameters

Name	Type	Description
`arr`	`array`	The array
`key`	`string`	Field to compare

Returns: number

Example

lolo

(array/max [{"price":3},{"price":9}] "price")

`array/min`

Minimum value (optionally by field)

lolo

(array/min arr key)

Parameters

Name	Type	Description
`arr`	`array`	The array
`key`	`string`	Field to compare

Returns: number

Example

lolo

(array/min [{"price":3},{"price":9}] "price")

`array/nearest`

Find the candidate vector nearest a query vector by cosine similarity. Returns { index, score, margin } — index/score of the best match, and margin (best score minus second-best), which is what makes an abstaining gate possible: a small margin means the top match is not confidently distinguished from the runner-up.

lolo

(array/nearest query candidates)

Parameters

Name	Type	Description
`query`	`array`	Query vector
`candidates`	`array`	Array of candidate vectors

Returns: object

Example

lolo

(array/nearest [1 0] [[1 0] [0 1]]) // => {"index": 0, "score": 1, "margin": 1}

`array/nth`

Get element at index (element type of input array, may be undefined out-of-bounds)

lolo

(array/nth arr index)

Parameters

Name	Type	Description
`arr`	`array`	The array
`index`	`number`	Index (0-based)

Returns: any

Example

lolo

(array/nth [1 2 3] 1) // => 2

`array/partition`

Split array by predicate into [matches, nonMatches]

lolo

(array/partition arr pred)

Parameters

Name	Type	Description
`arr`	`array`	The array
`pred`	`lambda`	Predicate function

Returns: array

Example

lolo

(array/partition [{"price":30},{"price":80}] ["fn","x",[">","@x.price",50]])

`array/prepend`

Add item to start (returns new array)

lolo

(array/prepend arr item)

Parameters

Name	Type	Description
`arr`	`array`	The array
`item`	`any`	Item to add

Returns: array

Example

lolo

(array/prepend [2 3] 1) // => [1, 2, 3]

`array/range`

Generate numbers: (range n) => [0,n); (range start end) => [start,end); optional step

lolo

(array/range n)

Parameters

Name	Type	Description
`n`	`number`	Upper bound or length (variadic)

Returns: array

Example

lolo

(array/range 3) // => [0 1 2]

`array/reduce`

Reduce array to single value (return type matches the lambda result / init type)

lolo

(array/reduce arr fn init)

Parameters

Name	Type	Description
`arr`	`array`	The array
`fn`	`lambda`	Reducer function (acc, item) => newAcc
`init`	`any`	Initial accumulator value

Returns: any

Example

lolo

(array/reduce [{"price":10},{"price":25}] 0 ["fn",["acc","x"],["+","@acc","@x.price"]])

`array/reject`

Remove elements matching predicate (returns same array element type as input)

lolo

(array/reject arr pred)

Parameters

Name	Type	Description
`arr`	`array`	The array
`pred`	`lambda`	Predicate function

Returns: array

Example

lolo

(array/reject [{"status":"active"},{"status":"deleted"}] ["fn","x",["=","@x.status","deleted"]])

`array/remove`

Remove item at index (returns new array)

lolo

(array/remove arr index)

Parameters

Name	Type	Description
`arr`	`array`	The array
`index`	`number`	Index to remove

Returns: array

Example

lolo

(array/remove [1 2 3] 1) // => [1, 3]

`array/removeItem`

Remove first matching item (returns new array)

lolo

(array/removeItem arr item)

Parameters

Name	Type	Description
`arr`	`array`	The array
`item`	`any`	Item to remove

Returns: array

Example

lolo

(array/removeItem [1 2 3 2] 2) // => [1, 3, 2]

`array/reverse`

Reverse array order (returns new array)

lolo

(array/reverse arr)

Parameters

Name	Type	Description
`arr`	`array`	The array

Returns: array

Example

lolo

(array/reverse [1 2 3]) // => [3, 2, 1]

`array/shuffle`

Randomly shuffle array (returns new array)

lolo

(array/shuffle arr)

Parameters

Name	Type	Description
`arr`	`array`	The array

Returns: array

Example

lolo

(array/shuffle [1 2 3 4 5])

`array/slice`

Extract subarray

lolo

(array/slice arr start end)

Parameters

Name	Type	Description
`arr`	`array`	The array
`start`	`number`	Start index
`end`	`number`	End index (exclusive)

Returns: array

Example

lolo

(array/slice [1 2 3 4] 1 3) // => [2, 3]

`array/some`

Check if any element matches predicate

lolo

(array/some arr pred)

Parameters

Name	Type	Description
`arr`	`array`	The array
`pred`	`lambda`	Predicate function

Returns: boolean

Example

lolo

(array/some [{"status":"archived"},{"status":"active"}] ["fn","x",["=","@x.status","active"]])

`array/sort`

Sort array (returns new array)

lolo

(array/sort arr key dir)

Parameters

Name	Type	Description
`arr`	`array`	The array
`key`	`string`	Field to sort by (for objects)
`dir`	`string`	"asc" or "desc"

Returns: array

Example

lolo

(array/sort [{"price":3},{"price":9},{"price":5}] "price" "desc")

`array/sum`

Sum values (optionally by field)

lolo

(array/sum arr key)

Parameters

Name	Type	Description
`arr`	`array`	The array
`key`	`string`	Field to sum

Returns: number

Example

lolo

(array/sum [{"price":10},{"price":25}] "price")

`array/take`

Take first n elements

lolo

(array/take arr n)

Parameters

Name	Type	Description
`arr`	`array`	The array
`n`	`number`	Number of elements

Returns: array

Example

lolo

(array/take [1,2,3,4,5,6,7] 5)

`array/takeLast`

Take last n elements

lolo

(array/takeLast arr n)

Parameters

Name	Type	Description
`arr`	`array`	The array
`n`	`number`	Number of elements

Returns: array

Example

lolo

(array/takeLast [1,2,3,4,5] 3)

`array/unique`

Remove duplicates (returns new array)

lolo

(array/unique arr)

Parameters

Name	Type	Description
`arr`	`array`	The array

Returns: array

Example

lolo

(array/unique [1 2 2 3 1]) // => [1, 2, 3]

`array/zip`

Pair elements from two arrays

lolo

(array/zip arr1 arr2)

Parameters

Name	Type	Description
`arr1`	`array`	First array
`arr2`	`array`	Second array

Returns: array

Example

lolo

(array/zip [1 2] (a "b")) // => [[1, "a"], [2, "b"]]

data/

`data/augment`

Apply data augmentation

lolo

(data/augment data config)

Parameters

Name	Type	Description
`data`	`object`	Data object
`config`	`object`	Augmentation config

Returns: object

Example

lolo

(data/augment [[1.0,2.0],[3.0,4.0]] {"flip":true,"rotate":15}) // => {}

`data/dataloader`

Create batched dataloader from dataset

lolo

(data/dataloader dataset batchSize)

Parameters

Name	Type	Description
`dataset`	`object`	Dataset to load
`batchSize`	`number`	Batch size

Returns: object

Example

lolo

(data/dataloader ["data/dataset",[[1,2],[3,4],[5,6]],{}] {"batch-size":2,"shuffle":true})

`data/dataset`

Create dataset from entity collection and contracts

lolo

(data/dataset entities schema)

Parameters

Name	Type	Description
`entities`	`array`	Entity collection
`schema`	`object`	Data schema

Returns: object

Example

lolo

(data/dataset [{"x":1,"y":2}] {"input":{"fields":["x"]},"output":{"fields":["y"]}})

`data/normalize`

Normalize features (mean/std or min/max)

lolo

(data/normalize tensor mode)

Parameters

Name	Type	Description
`tensor`	`object`	Input tensor
`mode`	`string`	Normalization mode

Returns: tensor

Example

lolo

(data/normalize [[1,2],[3,4]] {"method":"standard"})

`data/pad`

Pad sequences to uniform length

lolo

(data/pad sequences maxLen)

Parameters

Name	Type	Description
`sequences`	`array`	Sequences to pad
`maxLen`	`number`	Target length

Returns: tensor

Example

lolo

(data/pad [[1,2,3],[4,5]] {"max-length":4,"pad-value":0})

`data/split`

Train/validation split. Config carries trainRatio (default 0.8); the remainder is the validation split.

lolo

(data/split dataset config)

Parameters

Name	Type	Description
`dataset`	`object`	Dataset to split
`config`	`object`	Split config

Returns: array

Example

lolo

(data/split ["data/dataset",[1,2,3,4,5],{}] {"trainRatio":0.8})

`data/tokenize`

Tokenize text fields

lolo

(data/tokenize texts vocab)

Parameters

Name	Type	Description
`texts`	`array`	Texts to tokenize
`vocab`	`object`	Vocabulary mapping

Returns: tensor

Example

lolo

(data/tokenize "hello world" {"method":"bpe","max-length":512})

json/

`json/parse`

Parse a JSON string into a value; invalid JSON or non-string input returns null (never throws)

lolo

(json/parse s)

Parameters

Name	Type	Description
`s`	`string`	The JSON string to parse

Returns: any

Example

lolo

(json/parse "{\"a\": 1}") // => {a: 1}

`json/stringify`

Serialize any value to a JSON string

lolo

(json/stringify v)

Parameters

Name	Type	Description
`v`	`any`	The value to serialize

Returns: string

Example

lolo

["json/stringify", {a: 1}] // => "{\"a\":1}"

math/

`math/abs`

Absolute value

lolo

(math/abs n)

Parameters

Name	Type	Description
`n`	`number`	The number

Returns: number

Example

lolo

(math/abs -5) // => 5

`math/acos`

Arccosine (inverse cosine) in radians

lolo

(math/acos x)

Parameters

Name	Type	Description
`x`	`number`	Input value between -1 and 1

Returns: number

Example

lolo

(math/acos 0.5) // => 1.0472

`math/approach`

Move cur toward target by at most maxDelta

lolo

(math/approach cur target max)

Parameters

Name	Type	Description
`cur`	`number`	Current value
`target`	`number`	Target value
`max`	`number`	Maximum delta per step

Returns: number

Example

lolo

(math/approach 10 20 3) // => 13

`math/asin`

Arcsine (inverse sine) in radians

lolo

(math/asin x)

Parameters

Name	Type	Description
`x`	`number`	Input value between -1 and 1

Returns: number

Example

lolo

(math/asin 0.5) // => 0.5236

`math/atan`

Arctangent (inverse tangent) in radians

lolo

(math/atan x)

Parameters

Name	Type	Description
`x`	`number`	Input value

Returns: number

Example

lolo

(math/atan 1) // => 0.7854

`math/atan2`

Angle in radians from the positive x-axis to point (x, y)

lolo

(math/atan2 y x)

Parameters

Name	Type	Description
`y`	`number`	Y coordinate
`x`	`number`	X coordinate

Returns: number

Example

lolo

(math/atan2 1 1) // => 0.7854

`math/ceil`

Round up to integer

lolo

(math/ceil n)

Parameters

Name	Type	Description
`n`	`number`	The number

Returns: number

Example

lolo

(math/ceil 3.2) // => 4

`math/clamp`

Constrain value to range [min, max]

lolo

(math/clamp n min max)

Parameters

Name	Type	Description
`n`	`number`	The value to clamp
`min`	`number`	Minimum bound
`max`	`number`	Maximum bound

Returns: number

Example

lolo

(math/clamp 150 0 100) // => 100

`math/cos`

Cosine of an angle in radians

lolo

(math/cos radians)

Parameters

Name	Type	Description
`radians`	`number`	Angle in radians

Returns: number

Example

lolo

(math/cos 0) // => 1

`math/default`

Return default if value is null, undefined, or NaN

lolo

(math/default default)

Parameters

Name	Type	Description
`default`	`number`	Default value

Returns: number

Example

lolo

(math/default null 0) // => 0

`math/deg-rad`

Convert degrees to radians

lolo

(math/deg-rad degrees)

Parameters

Name	Type	Description
`degrees`	`number`	Angle in degrees

Returns: number

Example

lolo

(math/deg-rad 180) // => 3.1416

`math/floor`

Round down to integer

lolo

(math/floor n)

Parameters

Name	Type	Description
`n`	`number`	The number

Returns: number

Example

lolo

(math/floor 3.7) // => 3

`math/hypot`

Euclidean length sqrt(a²+b²)

lolo

(math/hypot a b)

Parameters

Name	Type	Description
`a`	`number`	First side
`b`	`number`	Second side

Returns: number

Example

lolo

(math/hypot 3 4) // => 5

`math/lerp`

Linear interpolation between a and b by factor t

lolo

(math/lerp a b t)

Parameters

Name	Type	Description
`a`	`number`	Start value
`b`	`number`	End value
`t`	`number`	Interpolation factor (0-1)

Returns: number

Example

lolo

(math/lerp 0 100 0.5) // => 50

`math/ln`

Natural logarithm (base e)

lolo

(math/ln n)

Parameters

Name	Type	Description
`n`	`number`	The number

Returns: number

Example

lolo

(math/ln 2.718281828) // => 1

`math/log10`

Base-10 logarithm

lolo

(math/log10 n)

Parameters

Name	Type	Description
`n`	`number`	The number

Returns: number

Example

lolo

(math/log10 100) // => 2

`math/map`

Map value from one range to another

lolo

(math/map n inMin inMax outMin outMax)

Parameters

Name	Type	Description
`n`	`number`	The value
`inMin`	`number`	Input range minimum
`inMax`	`number`	Input range maximum
`outMin`	`number`	Output range minimum
`outMax`	`number`	Output range maximum

Returns: number

Example

lolo

(math/map 5 0 10 0 100) // => 50

`math/max`

Maximum of values

lolo

(math/max ...nums)

Parameters

Name	Type	Description
`...nums`	`number[]`	Numbers to compare

Returns: number

Example

lolo

(math/max 3 1 4) // => 4

`math/min`

Minimum of values

lolo

(math/min ...nums)

Parameters

Name	Type	Description
`...nums`	`number[]`	Numbers to compare

Returns: number

Example

lolo

(math/min 3 1 4) // => 1

`math/mod`

Modulo (remainder)

lolo

(math/mod a b)

Parameters

Name	Type	Description
`a`	`number`	Dividend
`b`	`number`	Divisor

Returns: number

Example

lolo

(math/mod 7 3) // => 1

`math/pow`

Exponentiation (base^exp)

lolo

(math/pow base exp)

Parameters

Name	Type	Description
`base`	`number`	The base
`exp`	`number`	The exponent

Returns: number

Example

lolo

(math/pow 2 8) // => 256

`math/rad-deg`

Convert radians to degrees

lolo

(math/rad-deg radians)

Parameters

Name	Type	Description
`radians`	`number`	Angle in radians

Returns: number

Example

lolo

(math/rad-deg 3.1416) // => 180

`math/random`

Random number between 0 (inclusive) and 1 (exclusive)

lolo

(math/random)

Returns: number

Example

lolo

(math/random) // => 0.7234...

`math/randomInt`

Random integer in range [min, max] (inclusive)

lolo

(math/randomInt min max)

Parameters

Name	Type	Description
`min`	`number`	Minimum (inclusive)
`max`	`number`	Maximum (inclusive)

Returns: number

Example

lolo

(math/randomInt 1 6) // => 4

`math/round`

Round to nearest integer or specified decimals

lolo

(math/round n decimals)

Parameters

Name	Type	Description
`n`	`number`	The number
`decimals`	`number`	Decimal places

Returns: number

Example

lolo

(math/round 3.456 2) // => 3.46

`math/sign`

Returns -1, 0, or 1 indicating sign

lolo

(math/sign n)

Parameters

Name	Type	Description
`n`	`number`	The number

Returns: number

Example

lolo

(math/sign -42) // => -1

`math/sin`

Sine of an angle in radians

lolo

(math/sin radians)

Parameters

Name	Type	Description
`radians`	`number`	Angle in radians

Returns: number

Example

lolo

(math/sin 1.5708) // => 1

`math/sqrt`

Square root

lolo

(math/sqrt n)

Parameters

Name	Type	Description
`n`	`number`	The number

Returns: number

Example

lolo

(math/sqrt 16) // => 4

`math/tan`

Tangent of an angle in radians

lolo

(math/tan radians)

Parameters

Name	Type	Description
`radians`	`number`	Angle in radians

Returns: number

Example

lolo

(math/tan 0.7854) // => 1

`math/wrap`

Wrap a value into the half-open range [min, max)

lolo

(math/wrap value min max)

Parameters

Name	Type	Description
`value`	`number`	Value to wrap
`min`	`number`	Minimum bound
`max`	`number`	Maximum bound

Returns: number

Example

lolo

(math/wrap 15 0 10) // => 5

object/

`object/clone`

Shallow clone object

lolo

(object/clone obj)

Parameters

Name	Type	Description
`obj`	`object`	The object

Returns: any

Example

lolo

(object/clone {"a":1,"b":2})

`object/deepClone`

Deep clone object

lolo

(object/deepClone obj)

Parameters

Name	Type	Description
`obj`	`object`	The object

Returns: any

Example

lolo

(object/deepClone {"a":{"b":2}})

`object/deepMerge`

Deep merge objects (later wins)

lolo

(object/deepMerge ...objs)

Parameters

Name	Type	Description
`...objs`	`object[]`	Objects to merge

Returns: any

Example

lolo

(object/deepMerge {"a": {"b": 1}} {"a": {"c": 2}})

`object/entries`

Get [key, value] pairs as array

lolo

(object/entries obj)

Parameters

Name	Type	Description
`obj`	`object`	The object

Returns: array

Example

lolo

(object/entries {"a": 1}) // => [["a", 1]]

`object/equals`

Deep equality check

lolo

(object/equals a b)

Parameters

Name	Type	Description
`a`	`object`	First object
`b`	`object`	Second object

Returns: boolean

Example

lolo

(object/equals {"a": 1} {"a": 1}) // => true

`object/filter`

Filter entries by predicate

lolo

(object/filter obj pred)

Parameters

Name	Type	Description
`obj`	`object`	The object
`pred`	`lambda`	Predicate (key, value) => boolean

Returns: any

Example

lolo

(object/filter {"a":1,"b":null} ["fn",["k","v"],["!=","@v",null]])

`object/fromEntries`

Create object from [key, value] pairs

lolo

(object/fromEntries entries)

Parameters

Name	Type	Description
`entries`	`array`	Array of [key, value] pairs

Returns: any

Example

lolo

(object/fromEntries [["a" 1] ["b" 2]]) // => {"a": 1, "b": 2}

`object/get`

Get nested value by path (return type derived from input object shape and key)

lolo

(object/get obj path default)

Parameters

Name	Type	Description
`obj`	`object`	The object
`path`	`string`	Dot-separated path (e.g., "user.name")
`default`	`any`	Default if path not found

Returns: any

Example

lolo

(object/get {"profile":{"name":"Ann"}} "profile.name" "Anonymous")

`object/has`

Check if path exists

lolo

(object/has obj path)

Parameters

Name	Type	Description
`obj`	`object`	The object
`path`	`string`	Dot-separated path

Returns: boolean

Example

lolo

(object/has {"profile":{"name":"Ann"}} "profile.name")

`object/keys`

Get object keys as array

lolo

(object/keys obj)

Parameters

Name	Type	Description
`obj`	`object`	The object

Returns: array

Example

lolo

(object/keys {"a":1,"b":2}) // => ["a", "b"]

`object/mapKeys`

Transform all keys

lolo

(object/mapKeys obj fn)

Parameters

Name	Type	Description
`obj`	`object`	The object
`fn`	`lambda`	Transform function

Returns: any

Example

lolo

(object/mapKeys {"a":1,"b":2} ["fn","k",["str/upper","@k"]])

`object/mapValues`

Transform all values

lolo

(object/mapValues obj fn)

Parameters

Name	Type	Description
`obj`	`object`	The object
`fn`	`lambda`	Transform function

Returns: any

Example

lolo

(object/mapValues {"a":0.5,"b":0.25} ["fn","v",["*","@v",100]])

`object/merge`

Shallow merge objects (later wins)

lolo

(object/merge ...objs)

Parameters

Name	Type	Description
`...objs`	`object[]`	Objects to merge

Returns: any

Example

lolo

(object/merge {"a": 1} {"b": 2}) // => {"a": 1, "b": 2}

`object/omit`

Exclude specified keys

lolo

(object/omit obj keys)

Parameters

Name	Type	Description
`obj`	`object`	The object
`keys`	`array`	Keys to exclude

Returns: any

Example

lolo

(object/omit {"name":"Ann","password":"x"} ["password"])

`object/pick`

Select only specified keys (return type is subset of input object shape)

lolo

(object/pick obj keys)

Parameters

Name	Type	Description
`obj`	`object`	The object
`keys`	`array`	Keys to keep

Returns: any

Example

lolo

(object/pick {"name":"Ann","email":"ann@example.com","age":30} ["name","email"])

`object/set`

Set nested value by path (returns new object)

lolo

(object/set obj path value)

Parameters

Name	Type	Description
`obj`	`object`	The object
`path`	`string`	Dot-separated path
`value`	`any`	Value to set

Returns: any

Example

lolo

(object/set {"profile":{"name":"Ann"}} "profile.name" "John")

`object/values`

Get object values as array

lolo

(object/values obj)

Parameters

Name	Type	Description
`obj`	`object`	The object

Returns: array

Example

lolo

(object/values {"a":1,"b":2}) // => [1, 2]

path/

`path/astar`

A* shortest path on a w×h grid; returns cells start→goal (incl. both) or [] if none

lolo

(path/astar width height grid start goal)

Parameters

Name	Type	Description
`width`	`number`	Grid width
`height`	`number`	Grid height
`grid`	`array`	Grid data
`start`	`array`	Start coordinates
`goal`	`array`	Goal coordinates (variadic)

Returns: array

Example

lolo

(path/astar {"x":0,"y":0} {"x":2,"y":0} [] 3 1)

`path/reachable`

BFS cells reachable within N moves from start (incl. start); sorted row-major

lolo

(path/reachable width height grid start moves)

Parameters

Name	Type	Description
`width`	`number`	Grid width
`height`	`number`	Grid height
`grid`	`array`	Grid data
`start`	`array`	Start coordinates
`moves`	`number`	Maximum moves (variadic)

Returns: array

Example

lolo

(path/reachable {"x":1,"y":1} 1 [] 3 3 false)

str/

`str/camelCase`

Convert to camelCase

lolo

(str/camelCase s)

Parameters

Name	Type	Description
`s`	`string`	The string

Returns: string

Example

lolo

(str/camelCase "hello world") // => "helloWorld"

`str/capitalize`

Capitalize first character

lolo

(str/capitalize s)

Parameters

Name	Type	Description
`s`	`string`	The string

Returns: string

Example

lolo

(str/capitalize "hello") // => "Hello"

`str/concat`

Concatenate strings together

lolo

(str/concat str)

Parameters

Name	Type	Description
`str`	`string`	String to concatenate (variadic)

Returns: string

Example

lolo

(str/concat "Hello" " " "World") // => "Hello World"

`str/default`

Return default if value is null/undefined/empty

lolo

(str/default default)

Parameters

Name	Type	Description
`default`	`string`	Default value

Returns: string

Example

lolo

(str/default null "N/A") // => "N/A"

`str/endsWith`

Check if string ends with suffix

lolo

(str/endsWith s suffix)

Parameters

Name	Type	Description
`s`	`string`	The string
`suffix`	`string`	Suffix to check

Returns: boolean

Example

lolo

(str/endsWith "hello" "lo") // => true

`str/includes`

Check if string contains substring

lolo

(str/includes s search)

Parameters

Name	Type	Description
`s`	`string`	The string
`search`	`string`	Substring to find

Returns: boolean

Example

lolo

(str/includes "hello world" "world") // => true

`str/join`

Join array elements into string

lolo

(str/join arr delim)

Parameters

Name	Type	Description
`arr`	`array`	Array to join
`delim`	`string`	Delimiter

Returns: string

Example

lolo

(str/join (a "b" "c") ", ") // => "a, b, c"

`str/kebabCase`

Convert to kebab-case

lolo

(str/kebabCase s)

Parameters

Name	Type	Description
`s`	`string`	The string

Returns: string

Example

lolo

(str/kebabCase "Hello World") // => "hello-world"

`str/len`

String length

lolo

(str/len s)

Parameters

Name	Type	Description
`s`	`string`	The string

Returns: number

Example

lolo

(str/len "hello") // => 5

`str/lower`

Convert to lowercase

lolo

(str/lower s)

Parameters

Name	Type	Description
`s`	`string`	The string

Returns: string

Example

lolo

(str/lower "HELLO") // => "hello"

`str/padEnd`

Pad string from end to target length

lolo

(str/padEnd s len char)

Parameters

Name	Type	Description
`s`	`string`	The string
`len`	`number`	Target length
`char`	`string`	Padding character

Returns: string

Example

lolo

(str/padEnd "5" 3 "0") // => "500"

`str/padStart`

Pad string from start to target length

lolo

(str/padStart s len char)

Parameters

Name	Type	Description
`s`	`string`	The string
`len`	`number`	Target length
`char`	`string`	Padding character

Returns: string

Example

lolo

(str/padStart "5" 3 "0") // => "005"

`str/repeat`

Repeat string n times

lolo

(str/repeat s count)

Parameters

Name	Type	Description
`s`	`string`	The string
`count`	`number`	Repeat count

Returns: string

Example

lolo

(str/repeat "ab" 3) // => "ababab"

`str/replace`

Replace first occurrence

lolo

(str/replace s find replace)

Parameters

Name	Type	Description
`s`	`string`	The string
`find`	`string`	String to find
`replace`	`string`	Replacement

Returns: string

Example

lolo

(str/replace "hello world" "world" "there") // => "hello there"

`str/replaceAll`

Replace all occurrences

lolo

(str/replaceAll s find replace)

Parameters

Name	Type	Description
`s`	`string`	The string
`find`	`string`	String to find
`replace`	`string`	Replacement

Returns: string

Example

lolo

(str/replaceAll "a-b-c" "-" "_") // => "a_b_c"

`str/reverse`

Reverse string

lolo

(str/reverse s)

Parameters

Name	Type	Description
`s`	`string`	The string

Returns: string

Example

lolo

(str/reverse "hello") // => "olleh"

`str/slice`

Extract substring

lolo

(str/slice s start end)

Parameters

Name	Type	Description
`s`	`string`	The string
`start`	`number`	Start index
`end`	`number`	End index (exclusive)

Returns: string

Example

lolo

(str/slice "hello" 1 4) // => "ell"

`str/snakeCase`

Convert to snake_case

lolo

(str/snakeCase s)

Parameters

Name	Type	Description
`s`	`string`	The string

Returns: string

Example

lolo

(str/snakeCase "Hello World") // => "hello_world"

`str/split`

Split string into array by delimiter

lolo

(str/split s delim)

Parameters

Name	Type	Description
`s`	`string`	The string
`delim`	`string`	Delimiter

Returns: array

Example

lolo

(str/split "a,b,c" ",") // => ["a", "b", "c"]

`str/startsWith`

Check if string starts with prefix

lolo

(str/startsWith s prefix)

Parameters

Name	Type	Description
`s`	`string`	The string
`prefix`	`string`	Prefix to check

Returns: boolean

Example

lolo

(str/startsWith "hello" "hel") // => true

`str/template`

Variable substitution in template string

lolo

(str/template template vars)

Parameters

Name	Type	Description
`template`	`string`	Template with {placeholders}
`vars`	`object`	Variables to substitute

Returns: string

Example

lolo

(str/template "Hello, {name}!" {"name":"World"}) // => "Hello, World!"

`str/titleCase`

Convert to Title Case

lolo

(str/titleCase s)

Parameters

Name	Type	Description
`s`	`string`	The string

Returns: string

Example

lolo

(str/titleCase "hello world") // => "Hello World"

`str/trim`

Remove leading and trailing whitespace

lolo

(str/trim s)

Parameters

Name	Type	Description
`s`	`string`	The string

Returns: string

Example

lolo

(str/trim " hello ") // => "hello"

`str/trimEnd`

Remove trailing whitespace

lolo

(str/trimEnd s)

Parameters

Name	Type	Description
`s`	`string`	The string

Returns: string

Example

lolo

(str/trimEnd "hello ") // => "hello"

`str/trimStart`

Remove leading whitespace

lolo

(str/trimStart s)

Parameters

Name	Type	Description
`s`	`string`	The string

Returns: string

Example

lolo

(str/trimStart " hello") // => "hello"

`str/truncate`

Truncate string with optional suffix

lolo

(str/truncate s len suffix)

Parameters

Name	Type	Description
`s`	`string`	The string
`len`	`number`	Maximum length
`suffix`	`string`	Suffix for truncated strings

Returns: string

Example

lolo

(str/truncate "Hello World" 8 "...") // => "Hello..."

`str/upper`

Convert to uppercase

lolo

(str/upper s)

Parameters

Name	Type	Description
`s`	`string`	The string

Returns: string

Example

lolo

(str/upper "hello") // => "HELLO"

Core

Time and format

Orb

The language where the rule is the program.

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