/**
 * Casts the input to a string.
 *
 * @example
 * string(123) // "123"
 * 123|string // "123"
 * @group Conversion
 *
 * @param input The input can be any type.
 * @param prettify If true, the output will be pretty-printed.
 * @returns The input converted to a JSON string representation.
 */
export declare const toString: (input: unknown, prettify?: boolean) => string;
/**
 * Parses the string and returns a JSON object.
 *
 * @example
 * toJson('{"key": "value"}') // { key: "value" }
 * '{"name": "John", "age": 30}'|toJson // { name: "John", age: 30 }
 * @group Conversion
 *
 * @param input The JSON string to parse.
 * @returns The parsed JSON object or value.
 * @throws {SyntaxError} If the string is not valid JSON.
 */
export declare const toJson: (input: string) => any;
/**
 * Returns the number of characters in a string, or the length of an array.
 *
 * @example
 * length("hello") // 5
 * length([1, 2, 3]) // 3
 * @group Utility
 *
 * @param input The input can be a string, an array, or an object.
 * @returns The number of characters in a string, or the length of an array.
 */
export declare const length: (input: unknown) => number;
/**
 * Gets a substring of a string.
 *
 * @example
 * substring("hello world", 0, 5) // "hello"
 * @group String
 *
 * @param input The input string.
 * @param start The starting index of the substring.
 * @param length The length of the substring.
 * @returns The substring of the input string.
 */
export declare const substring: (input: unknown, start: number, length: number | undefined) => string;
/**
 * Returns the substring before the first occurrence of the character sequence chars in str.
 *
 * @example substringBefore("hello world", " ") // "hello"
 * @group String
 * @param input The input string.
 * @param chars The character sequence to search for.
 * @returns The substring before the first occurrence of the character sequence chars in str.
 */
export declare const substringBefore: (input: unknown, chars: unknown) => string;
/**
 * Returns the substring after the first occurrence of the character sequence chars in str.
 *
 * @example
 * substringAfter("hello world", " ") // "world"
 * @group String
 *
 * @param input The input string.
 * @param chars The character sequence to search for.
 * @returns The substring after the first occurrence of the character sequence chars in str.
 */
export declare const substringAfter: (input: unknown, chars: unknown) => string;
/**
 * Converts the input string to uppercase.
 *
 * @example
 * uppercase("hello") // "HELLO"
 * "hello world"|uppercase // "HELLO WORLD"
 * @group String
 *
 * @param input The input to convert to uppercase. Non-string inputs are converted to JSON string first.
 * @returns The uppercase string.
 */
export declare const uppercase: (input: unknown) => string;
/**
 * Converts the input string to lowercase.
 *
 * @example
 * lowercase("HELLO") // "hello"
 * "HELLO WORLD"|lowercase // "hello world"
 * @group String
 *
 * @param input The input to convert to lowercase. Non-string inputs are converted to JSON string first.
 * @returns The lowercase string.
 */
export declare const lowercase: (input: unknown) => string;
/**
 * Converts the input string to camel case.
 *
 * @example
 * camelCase("foo bar") // "fooBar"
 * "hello-world"|camelCase // "helloWorld"
 * camelCase("HELLO_WORLD") // "helloWorld"
 * @group String
 *
 * @param input The input string to convert to camel case.
 * @returns The camel case string, or empty string if input is not a string.
 */
export declare const camelCase: (input: unknown) => string;
/**
 * Converts the input string to pascal case.
 *
 * @example
 * pascalCase("foo bar") // "FooBar"
 * "hello-world"|pascalCase // "HelloWorld"
 * pascalCase("HELLO_WORLD") // "HelloWorld"
 * @group String
 *
 * @param input The input string to convert to pascal case.
 * @returns The pascal case string, or empty string if input is not a string.
 */
export declare const pascalCase: (input: unknown) => string;
/**
 * Trims whitespace from both ends of a string.
 *
 * @example
 * trim("  hello  ") // "hello"
 * "  world  "|trim // "world"
 * trim("__hello__", "_") // "hello"
 * @group String
 *
 * @param input The input string to trim.
 * @param trimChar Optional character to trim instead of whitespace.
 * @returns The trimmed string, or empty string if input is not a string.
 */
export declare const trim: (input: unknown, trimChar?: string) => string;
/**
 * Pads the input string to the specified width.
 *
 * @example
 * pad("hello", 10) // "hello     "
 * pad("world", -8, "0") // "000world"
 * "foo"|pad(5, ".") // "foo.."
 * @group String
 *
 * @param input The input to pad. Non-string inputs are converted to JSON string first.
 * @param width The target width. Positive values pad to the right, negative values pad to the left.
 * @param char The character to use for padding. Defaults to space.
 * @returns The padded string.
 */
export declare const pad: (input: unknown, width: number, char?: string) => string;
/**
 * Checks if the input string or array contains the specified value.
 *
 * @example
 * contains("hello world", "world") // true
 * "foo-bar"|contains("bar") // true
 * contains([1, 2, 3], 2) // true
 * @group String
 *
 * @param input The input string or array to search in.
 * @param search The value to search for.
 * @returns True if the input contains the search value, false otherwise.
 */
export declare const contains: (input: unknown, search: string) => boolean;
/**
 * Checks if the input string starts with the specified substring.
 *
 * @example
 * startsWith("hello world", "hello") // true
 * "foo-bar"|startsWith("foo") // true
 * startsWith("test", "xyz") // false
 * @group String
 *
 * @param input The input string to check.
 * @param search The substring to search for at the beginning.
 * @returns True if the input starts with the search string, false otherwise.
 */
export declare const startsWith: (input: unknown, search: string) => boolean;
/**
 * Checks if the input string ends with the specified substring.
 *
 * @example
 * endsWith("hello world", "world") // true
 * "foo-bar"|endsWith("bar") // true
 * endsWith("test", "xyz") // false
 * @group String
 *
 * @param input The input string to check.
 * @param search The substring to search for at the end.
 * @returns True if the input ends with the search string, false otherwise.
 */
export declare const endsWith: (input: unknown, search: string) => boolean;
/**
 * Splits the input string into an array of substrings.
 *
 * @example
 * split("foo,bar,baz", ",") // ["foo", "bar", "baz"]
 * "one-two-three"|split("-") // ["one", "two", "three"]
 * split("hello world", " ") // ["hello", "world"]
 * @group String
 *
 * @param input The input string to split.
 * @param separator The separator string to split on.
 * @returns An array of substrings, or empty array if input is not a string.
 */
export declare const split: (input: unknown, separator: string) => string[];
/**
 * Joins elements of an array into a string.
 *
 * @example
 * arrayJoin(["foo", "bar", "baz"], ",") // "foo,bar,baz"
 * ["one", "two", "three"]|arrayJoin("-") // "one-two-three"
 * arrayJoin([1, 2, 3]) // "1,2,3"
 * @group Array
 *
 * @param input The input array to join.
 * @param separator The separator string to use between elements. Defaults to comma.
 * @returns The joined string, or undefined if input is not an array.
 */
export declare const arrayJoin: (input: unknown, separator?: string) => string;
/**
 * Replaces occurrences of a specified string with a replacement string.
 *
 * @example
 * replace("foo-bar-baz", "-", "_") // "foo_bar_baz"
 * "hello world"|replace("world", "there") // "hello there"
 * replace("test test test", "test", "demo") // "demo demo demo"
 * @group String
 *
 * @param input The input string to perform replacements on.
 * @param search The string to search for and replace.
 * @param replacement The string to replace matches with. Defaults to empty string.
 * @returns The string with replacements made, or undefined if input is not a string.
 */
export declare const replace: (input: unknown, search: string, replacement: string) => string;
/**
 * Encodes a string to Base64.
 *
 * @example
 * base64Encode("hello") // "aGVsbG8="
 * "hello world"|base64Encode // "aGVsbG8gd29ybGQ="
 * base64Encode("test") // "dGVzdA=="
 * @group Encoding
 *
 * @param input The input string to encode.
 * @returns The Base64 encoded string, or empty string if input is not a string or encoding fails.
 */
export declare const base64Encode: (input: unknown) => string;
/**
 * Decodes a Base64 encoded string.
 *
 * @example
 * base64Decode("aGVsbG8=") // "hello"
 * "aGVsbG8gd29ybGQ="|base64Decode // "hello world"
 * base64Decode("dGVzdA==") // "test"
 * @group Encoding
 *
 * @param input The Base64 encoded string to decode.
 * @returns The decoded string, or empty string if input is not a string.
 */
export declare const base64Decode: (input: unknown) => string;
/**
 * Encodes a string or object to URI component format.
 *
 * @example
 * formUrlEncoded("hello world") // "hello%20world"
 * formUrlEncoded({name: "John", age: 30}) // "name=John&age=30"
 * "hello & world"|formUrlEncoded // "hello%20%26%20world"
 * @group Encoding
 *
 * @param input The input string or object to encode.
 * @returns The URL encoded string, or empty string if input is not a string or object.
 */
export declare const formUrlEncoded: (input: unknown) => string;
/**
 * Converts the input to a number.
 *
 * @example
 * toNumber("123") // 123
 * "45.67"|toNumber // 45.67
 * toNumber("abc") // NaN
 * @group Conversion
 *
 * @param input The input to convert to a number.
 * @returns The numeric value, or NaN if conversion fails.
 */
export declare const toNumber: (input: unknown) => number;
/**
 * Parses a string and returns an integer.
 *
 * @example
 * parseInteger("123") // 123
 * "45.67"|parseInteger // 45
 * parseInteger(123.89) // 123
 * @group Conversion
 *
 * @param input The input to parse as an integer.
 * @returns The integer value, or NaN if parsing fails.
 */
export declare const parseInteger: (input: unknown) => number;
/**
 * Returns the absolute value of a number.
 *
 * @example
 * absoluteValue(-5) // 5
 * (-10)|absoluteValue // 10
 * absoluteValue(3.14) // 3.14
 * @group Math
 *
 * @param input The input number to get the absolute value of.
 * @returns The absolute value, or NaN if input cannot be converted to a number.
 */
export declare const absoluteValue: (input: unknown) => number;
/**
 * Rounds a number down to the nearest integer.
 *
 * @example
 * floor(3.7) // 3
 * (3.14)|floor // 3
 * floor(-2.8) // -3
 * @group Math
 *
 * @param input The input number to round down.
 * @returns The rounded down integer, or NaN if input cannot be converted to a number.
 */
export declare const floor: (input: unknown) => number;
/**
 * Rounds a number up to the nearest integer.
 *
 * @example
 * ceil(3.2) // 4
 * (3.14)|ceil // 4
 * ceil(-2.8) // -2
 * @group Math
 *
 * @param input The input number to round up.
 * @returns The rounded up integer, or NaN if input cannot be converted to a number.
 */
export declare const ceil: (input: unknown) => number;
/**
 * Rounds a number to the nearest integer or to specified decimal places.
 *
 * @example
 * round(3.7) // 4
 * round(3.14159, 2) // 3.14
 * (2.567)|round // 3
 * @group Math
 *
 * @param input The input number to round.
 * @param decimals Optional number of decimal places to round to.
 * @returns The rounded number, or NaN if input cannot be converted to a number.
 */
export declare const round: (input: unknown, decimals?: number) => number;
/**
 * Returns the value of a number raised to a power.
 *
 * @example
 * power(2, 3) // 8
 * (2)|power(4) // 16
 * power(9) // 81 (defaults to power of 2)
 * @group Math
 *
 * @param input The base number.
 * @param exponent The exponent to raise the base to. Defaults to 2.
 * @returns The result of base raised to the exponent, or NaN if input cannot be converted to a number.
 */
export declare const power: (input: unknown, exponent?: number) => number;
/**
 * Returns the square root of a number.
 *
 * @example
 * sqrt(16) // 4
 * (25)|sqrt // 5
 * sqrt(2) // 1.4142135623730951
 * @group Math
 *
 * @param input The input number to get the square root of.
 * @returns The square root of the input, or NaN if input cannot be converted to a number.
 */
export declare const sqrt: (input: unknown) => number;
/**
 * Generates a random number between 0 (inclusive) and 1 (exclusive).
 *
 * @example
 * randomNumber() // 0.123456789 (example output)
 * randomNumber() // 0.987654321 (different each time)
 * @group Math
 *
 * @returns A random floating-point number between 0 and 1.
 */
export declare const randomNumber: () => number;
/**
 * Formats a number to a decimal representation as specified by the format string.
 *
 * @example
 * formatNumber(1234.567, "#,##0.00") // "1,234.57"
 * (1000)|formatNumber("0.00") // "1000.00"
 * formatNumber(42, "#,###") // "42"
 * @group Conversion
 *
 * @param input The input number to format.
 * @param format The format string specifying decimal places and grouping.
 * @returns The formatted number string, or empty string if input cannot be converted to a number.
 */
export declare const formatNumber: (input: unknown, format: string) => string;
/**
 * Formats a number as a string in the specified base.
 *
 * @example
 * formatBase(255, 16) // "ff"
 * (10)|formatBase(2) // "1010"
 * formatBase(64, 8) // "100"
 * @group Conversion
 *
 * @param input The input number to format.
 * @param base The numeric base to convert to (2-36).
 * @returns The number formatted in the specified base, or empty string if input cannot be converted to a number.
 */
export declare const formatBase: (input: unknown, base: number) => string;
/**
 * Formats a number as an integer with zero padding.
 *
 * @example
 * formatInteger(42, "000") // "042"
 * (7)|formatInteger("0000") // "0007"
 * formatInteger(123, "00") // "123"
 * @group Conversion
 *
 * @param input The input number to format.
 * @param format The format string indicating the minimum number of digits.
 * @returns The zero-padded integer string, or empty string if input cannot be converted to a number.
 */
export declare const formatInteger: (input: unknown, format: string) => string;
/**
 * Calculates the sum of an array of numbers.
 *
 * @example
 * sum([1, 2, 3, 4]) // 10
 * [1.5, 2.5, 3.0]|sum // 7
 * sum(1, 2, 3, 4) // 10
 * @group Math
 *
 * @param input The input array of numbers or individual number arguments.
 * @returns The sum of all numbers, or NaN if input is not an array.
 */
export declare const sum: (...input: unknown[]) => number;
/**
 * Finds the maximum value in an array of numbers.
 *
 * @example
 * max([1, 5, 3, 2]) // 5
 * [10, 20, 15]|max // 20
 * max(1, 5, 3, 2) // 5
 * @group Math
 *
 * @param input The input array of numbers or individual number arguments.
 * @returns The maximum value, or NaN if input is not an array.
 */
export declare const max: (...input: unknown[]) => number;
/**
 * Finds the minimum value in an array of numbers.
 *
 * @example
 * min([1, 5, 3, 2]) // 1
 * [10, 20, 15]|min // 10
 * min(1, 5, 3, 2) // 1
 * @group Math
 *
 * @param input The input array of numbers or individual number arguments.
 * @returns The minimum value, or NaN if input is not an array.
 */
export declare const min: (...input: unknown[]) => number;
/**
 * Calculates the average of an array of numbers.
 *
 * @example
 * average([1, 2, 3, 4]) // 2.5
 * [10, 20, 30]|average // 20
 * average(1, 2, 3, 4) // 2.5
 * @group Math
 *
 * @param input The input array of numbers or individual number arguments.
 * @returns The average value, or NaN if input is not an array.
 */
export declare const average: (...input: unknown[]) => number;
/**
 * Converts the input to a boolean.
 *
 * @example
 * toBoolean("true") // true
 * "false"|toBoolean // false
 * toBoolean(1) // true
 * toBoolean(0) // false
 * @group Conversion
 *
 * @param input The input to convert to a boolean.
 * @returns The boolean value, or undefined for ambiguous string values.
 */
export declare const toBoolean: (input: unknown) => boolean;
/**
 * Returns the logical NOT of the input.
 *
 * @example
 * not(true) // false
 * false|not // true
 * not(0) // true
 * not("") // true
 * @group Utility
 *
 * @param input The input to apply logical NOT to.
 * @returns The logical NOT of the input converted to boolean.
 */
export declare const not: (input: unknown) => boolean;
/**
 * Evaluates a list of predicates and returns the first result expression whose predicate is satisfied.
 *
 * @example
 * switch(expression, case1, result1, case2, result2, ..., default)
 * @group Utility
 *
 * @param args The arguments array where the first element is the expression to evaluate, followed by pairs of case and result, and optionally a default value.
 * @returns The result of the first case whose predicate is satisfied, or the default value if no case is satisfied.
 */
export declare const switchCase: (...args: unknown[]) => unknown;
/**
 * Returns a sub-array from start index to end index.
 *
 * @example
 * range([1, 2, 3, 4, 5], 1, 4) // [2, 3, 4]
 * [10, 20, 30, 40]|range(0, 2) // [10, 20]
 * range(["a", "b", "c", "d"], 2) // ["c", "d"]
 * @group Array
 *
 * @param array The input array.
 * @param start The starting index (inclusive).
 * @param end The ending index (exclusive). If not provided, slices to the end of the array.
 * @returns The sub-array from start to end, or empty array if input is not an array.
 */
export declare const arrayRange: (array: unknown[], start: number, end?: number) => unknown[];
/**
 * Appends elements to an array.
 *
 * @example
 * append([1, 2], 3) // [1, 2, 3]
 * [1, 2]|append(3, 4) // [1, 2, 3, 4]
 * append([], 1, 2, 3) // [1, 2, 3]
 * @group Array
 *
 * @param input The input values to append to an array.
 * @returns A new array with all inputs flattened and appended, or empty array if no valid input.
 */
export declare const arrayAppend: (...input: unknown[]) => unknown[];
/**
 * Reverses the elements of an array.
 *
 * @example
 * reverse([1, 2, 3]) // [3, 2, 1]
 * [1, 2, 3]|reverse // [3, 2, 1]
 * reverse(["a", "b", "c"]) // ["c", "b", "a"]
 * @group Array
 *
 * @param input The input values to reverse.
 * @returns A new array with elements in reverse order, or empty array if no valid input.
 */
export declare const arrayReverse: (...input: unknown[]) => unknown[];
/**
 * Shuffles the elements of an array randomly.
 *
 * @example
 * shuffle([1, 2, 3]) // [2, 1, 3] (random order)
 * [1, 2, 3]|shuffle // [3, 1, 2] (random order)
 * shuffle(["a", "b", "c"]) // ["c", "a", "b"] (random order)
 * @group Array
 *
 * @param input The input array to shuffle.
 * @returns The same array with elements randomly shuffled, or empty array if input is not an array.
 */
export declare const arrayShuffle: (input: unknown[]) => unknown[];
/**
 * Sorts the elements of an array.
 *
 * @example
 * sort([3, 1, 2]) // [1, 2, 3]
 * [3, 1, 2]|sort // [1, 2, 3]
 * sort([{age: 30}, {age: 20}], "age") // [{age: 20}, {age: 30}]
 * sort([{age: 30}, {age: 20}], "age", true) // [{age: 30}, {age: 20}]
 * @group Array
 *
 * @param input The input array to sort.
 * @param expression Optional JEXL expression to determine sort value for objects.
 * @param descending Optional flag to sort in descending order.
 * @returns A new sorted array, or empty array if input is not an array.
 */
export declare const arraySort: (input: unknown[], expression?: string, descending?: boolean) => unknown[];
/**
 * Returns a new array with duplicate elements removed.
 *
 * @example
 * distinct([1, 2, 2, 3, 1]) // [1, 2, 3]
 * [1, 2, 2, 3]|distinct // [1, 2, 3]
 * distinct(["a", "b", "a", "c"]) // ["a", "b", "c"]
 * @group Array
 *
 * @param input The input array to remove duplicates from.
 * @returns A new array with duplicates removed, or empty array if input is not an array.
 */
export declare const arrayDistinct: (input: unknown[]) => unknown[];
/**
 * Creates a new object based on key-value pairs or string keys.
 *
 * @example
 * toObject([["name", "John"], ["age", 30]]) // {name: "John", age: 30}
 * toObject("name", "John") // {name: "John"}
 * toObject(["key1", "key2"], "defaultValue") // {key1: "defaultValue", key2: "defaultValue"}
 *
 * @group Array
 *
 * @param input The input string key or array of key-value pairs.
 * @param val Optional default value for string keys or when array elements are strings.
 * @returns A new object created from the input, or empty object if input is invalid.
 */
export declare const arrayToObject: (input: unknown, val?: unknown) => any;
/**
 * Returns a new array with elements transformed by extracting a specific field.
 *
 * @example
 * mapField([{name: "John"}, {name: "Jane"}], "name") // ["John", "Jane"]
 * [{age: 30}, {age: 25}]|mapField("age") // [30, 25]
 * mapField([{x: 1, y: 2}, {x: 3, y: 4}], "x") // [1, 3]
 * @group Array
 *
 * @param input The input array of objects to extract fields from.
 * @param field The field name to extract from each object.
 * @returns A new array with extracted field values, or empty array if input is not an array.
 */
export declare const mapField: (input: unknown[], field: string) => any[];
/**
 * Returns an array containing the results of applying the expression parameter to each value in the array parameter.
 * The expression must be a valid JEXL expression string, which is applied to each element of the array.
 * The relative context provided to the expression is an object with the properties value, index and array (the original array).
 *
 * @example
 * map([1, 2, 3], "value * 2") // [2, 4, 6]
 * [{name: "John"}, {name: "Jane"}]|map("value.name") // ["John", "Jane"]
 * map([1, 2, 3], "value + index") // [1, 3, 5]
 * @group Array
 *
 * @param input The input array to transform.
 * @param expression The JEXL expression to apply to each element.
 * @returns A new array with transformed elements, or undefined if input is not an array.
 */
export declare const arrayMap: (input: unknown[], expression: string) => any[];
/**
 * Checks whether the provided array has any elements that match the specified expression.
 * The expression must be a valid JEXL expression string, and is applied to each element of the array.
 * The relative context provided to the expression is an object with the properties value, index and array (the original array).
 *
 * @example
 * any([1, 2, 3], "value > 2") // true
 * [{age: 25}, {age: 35}]|any("value.age > 30") // true
 * any([1, 2, 3], "value > 5") // false
 * @group Array
 *
 * @param input The input array to test.
 * @param expression The JEXL expression to test against each element  (supports value, index and array as context).
 * @returns True if any element matches the expression, false otherwise or if input is not an array.
 */
export declare const arrayAny: (input: unknown[], expression: string) => boolean;
/**
 * Checks whether the provided array has all elements that match the specified expression.
 * The expression must be a valid JEXL expression string, and is applied to each element of the array.
 * The relative context provided to the expression is an object with the properties value, index and array (the original array).
 *
 * @example
 * every([2, 4, 6], "value % 2 == 0") // true
 * [{age: 25}, {age: 35}]|every("value.age > 20") // true
 * every([1, 2, 3], "value > 2") // false
 * @group Array
 *
 * @param input The input array to test.
 * @param expression The JEXL expression to test against each element  (supports value, index and array as context).
 * @returns True if all elements match the expression, false otherwise or if input is not an array.
 */
export declare const arrayEvery: (input: unknown[], expression: string) => boolean;
/**
 * Returns a new array with the elements of the input array that match the specified expression.
 * The expression must be a valid JEXL expression string, and is applied to each element of the array.
 * The relative context provided to the expression is an object with the properties value, index and array (the original array).
 *
 * @example
 * filter([1, 2, 3, 4], "value > 2") // [3, 4]
 * [{age: 25}, {age: 35}]|filter("value.age > 30") // [{age: 35}]
 * filter([1, 2, 3, 4], "value % 2 == 0") // [2, 4]
 * @group Array
 *
 * @param input The input array to filter.
 * @param expression The JEXL expression to test against each element (supports value, index and array as context).
 * @returns A new array containing only elements that match the expression, or empty array if input is not an array.
 */
export declare const arrayFilter: (input: unknown[], expression: string) => unknown[];
/**
 * Finds the first element in an array that matches the specified expression.
 * The expression must be a valid JEXL expression string, and is applied to each element of the array.
 * The relative context provided to the expression is an object with the properties value, index and array (the original array).
 *
 * @example
 * find([1, 2, 3, 4], "value > 2") // 3
 * [{name: "John"}, {name: "Jane"}]|find("value.name == 'Jane'") // {name: "Jane"}
 * find([1, 2, 3], "value > 5") // undefined
 * @group Array
 *
 * @param input The input array to search.
 * @param expression The JEXL expression to test against each element  (supports value, index and array as context).
 * @returns The first element that matches the expression, or undefined if no match found or input is not an array.
 */
export declare const arrayFind: (input: unknown[], expression: string) => unknown;
/**
 *
 * Finds the index of the first element in the input array that satisfies the given Jexl expression.
 *
 * @example
 * [1, 2, 3, 4]|findIndex('value > 2'); // returns 2
 * @group Array
 *
 * @param input - The array to search through.
 * @param expression - A Jexl expression string to evaluate for each element. The expression has access to `value`, `index`, and `array`.
 * @returns The index of the first matching element, or `-1` if no element matches, or `undefined` if the input is not an array.
 */
export declare const arrayFindIndex: (input: unknown[], expression: string) => number;
/**
 * Returns an aggregated value derived from applying the function parameter successively to each value in array in combination with the result of the previous application of the function.
 * The expression must be a valid JEXL expression string, and behaves like an infix operator between each value within the array.
 * The relative context provided to the expression is an object with the properties accumulator, value, index and array (the original array).
 *
 * @example
 * reduce([1, 2, 3, 4], "accumulator + value", 0) // 10
 * [1, 2, 3]|reduce("accumulator * value", 1) // 6
 * reduce(["a", "b", "c"], "accumulator + value", "") // "abc"
 * @group Array
 *
 * @param input The input array to reduce.
 * @param expression The JEXL expression to apply for each reduction step.
 * @param initialValue The initial value for the accumulator.
 * @returns The final accumulated value, or undefined if input is not an array.
 */
export declare const arrayReduce: (input: unknown[], expression: string, initialValue: unknown) => unknown;
/**
 * Returns the keys of an object as an array.
 *
 * @example
 * keys({name: "John", age: 30}) // ["name", "age"]
 * {a: 1, b: 2}|keys // ["a", "b"]
 * keys({}) // []
 * @group Array
 *
 * @param input The input object to get keys from.
 * @returns An array of object keys, or undefined if input is not an object.
 */
export declare const objectKeys: (input: unknown) => string[];
/**
 * Returns the values of an object as an array.
 *
 * @example
 * values({name: "John", age: 30}) // ["John", 30]
 * {a: 1, b: 2}|values // [1, 2]
 * values({}) // []
 * @group Object
 *
 * @param input The input object to get values from.
 * @returns An array of object values, or undefined if input is not an object.
 */
export declare const objectValues: (input: unknown) => any[];
/**
 * Returns an array of key-value pairs from the input object.
 *
 * @example
 * entries({name: "John", age: 30}) // [["name", "John"], ["age", 30]]
 * {a: 1, b: 2}|entries // [["a", 1], ["b", 2]]
 * entries({}) // []
 * @group Object
 *
 * @param input The input object to get entries from.
 * @returns An array of [key, value] pairs, or undefined if input is not an object.
 */
export declare const objectEntries: (input: unknown) => [string, any][];
/**
 * Returns a new object with the properties of the input objects merged together.
 *
 * @example
 * merge({a: 1}, {b: 2}) // {a: 1, b: 2}
 * {a: 1}|merge({b: 2}, {c: 3}) // {a: 1, b: 2, c: 3}
 * merge({a: 1}, {a: 2}) // {a: 2} (later values override)
 * @group Object
 *
 * @param args The input objects to merge.
 * @returns A new object with all properties merged together.
 */
export declare const objectMerge: (...args: unknown[]) => Record<string, unknown>;
/**
 * Returns the current date and time in the ISO 8601 format.
 *
 * @example
 * now() // "2023-12-25T10:30:00.000Z"
 * now() // "2023-12-25T14:45:30.123Z" (different time)
 * @group DateTime
 *
 * @returns The current date and time as an ISO 8601 string.
 */
export declare const now: () => string;
/**
 * Returns the current date and time in milliseconds since the Unix epoch.
 *
 * @example
 * millis() // 1703505000000
 * millis() // 1703505123456 (different time)
 * @group DateTime
 *
 * @returns The current timestamp in milliseconds.
 */
export declare const millis: () => number;
/**
 * Parses the number of milliseconds since the Unix epoch or parses a string (with or without specified format) and returns the date and time in the ISO 8601 format.
 *
 * @example
 * toDateTime(1703505000000) // "2023-12-25T10:30:00.000Z"
 * toDateTime("2023-12-25") // "2023-12-25T00:00:00.000Z"
 * toDateTime("25/12/2023", "dd/MM/yyyy") // "2023-12-25T00:00:00.000Z"
 * toDateTime() // Current date/time (same as now())
 * @group DateTime
 *
 * @param input Optional timestamp in milliseconds or date string.
 * @param format Optional format string for parsing date strings.
 * @returns The date and time as an ISO 8601 string, or undefined if parsing fails.
 */
export declare const toDateTime: (input?: number | string, format?: string) => string;
/**
 * Converts a date and time to a provided format.
 *
 * @example
 * dateTimeFormat(datetime, format)
 * datetime|dateTimeFormat(format)
 * @group DateTime
 *
 * @param input The input date and time, either as a string or number.
 * @param format The format to convert the date and time to.
 * @returns The date and time in the specified format.
 */
export declare const dateTimeFormat: (input: number | string, format: string) => string | null;
/**
 * Parses the date and time in the ISO 8601 format and returns the number of milliseconds since the Unix epoch.
 *
 * @example
 * dateTimeToMillis("2023-12-25T10:30:00.000Z") // 1703505000000
 * "2023-01-01T00:00:00.000Z"|dateTimeToMillis // 1672531200000
 * dateTimeToMillis("2023-12-25") // 1703462400000
 * @group DateTime
 *
 * @param input The date and time string to parse.
 * @returns The timestamp in milliseconds since Unix epoch.
 */
export declare const dateTimeToMillis: (input: string) => number;
/**
 * Adds a time range to a date and time in the ISO 8601 format.
 *
 * @example
 * dateTimeAdd("2023-12-25T10:30:00.000Z", "day", 1) // "2023-12-26T10:30:00.000Z"
 * now()|dateTimeAdd("hour", -2) // Two hours ago
 * dateTimeAdd("2023-01-01T00:00:00.000Z", "month", 3) // "2023-04-01T00:00:00.000Z"
 * @group DateTime
 *
 * @param input The input date and time string in ISO 8601 format.
 * @param unit The time unit to add ("day", "hour", "minute", "second", "month", "year", etc.).
 * @param value The amount to add (can be negative to subtract).
 * @returns The new date and time as an ISO 8601 string.
 */
export declare const dateTimeAdd: (input: string, unit: string, value: number) => string;
/**
 * Converts an ISO datetime string to a target timezone, handling daylight savings, and returns an ISO string with the correct offset.
 *
 * @example
 * convertTimeZone('2025-06-26T12:00:00Z', 'Europe/Amsterdam') // 2025-06-26T14:00:00.0000000+02:00
 * '2025-06-26T12:00:00Z'|convertTimeZone('Pacific Standard Time') // '2025-06-26T05:00:00.0000000-07:00'
 * @group DateTime
 *
 * @param input ISO datetime string
 * @param targetTimeZone Target timezone (IANA or Windows ID or fixed offset)
 * @returns ISO datetime string with correct offset
 */
export declare const convertTimeZone: (input: unknown, targetTimeZone: unknown) => string | null;
/**
 * Converts a local time string in a specified timezone to an ISO datetime string with the correct offset.
 *
 * @example
 * localTimeToIsoWithOffset('2025-06-26 14:00:00', 'Europe/Amsterdam') // '2025-06-26T14:00:00.0000000+02:00'
 * '2025-06-26 05:00:00'|localTimeToIsoWithOffset('Pacific Standard Time') // '2025-06-26T05:00:00.0000000-08:00'
 * @group DateTime
 *
 * @param localTime Local time string
 * @param timeZone Timezone (IANA or Windows ID or fixed offset)
 * @returns ISO datetime string with correct offset
 */
export declare const localTimeToIsoWithOffset: (localTime: string, timeZone: string) => string | null;
/**
 * Evaluates a JEXL expression and returns the result.
 * If only one argument is provided, it is expected that the first argument is a JEXL expression.
 * If two arguments are provided, the first argument is the context (must be an object) and the second argument is the JEXL expression.
 * The expression uses the default JEXL extended grammar and can't use any custom defined functions or transforms.
 *
 * @example
 * _eval("1 + 2") // 3
 * _eval({x: 5, y: 10}, "x + y") // 15
 * "2 * 3"|_eval // 6
 * _eval({name: "John"}, "name") // "John"
 * @group Utility
 *
 * @param input Either a JEXL expression string or a context object.
 * @param expression Optional JEXL expression when first argument is context.
 * @returns The result of evaluating the expression, or undefined if evaluation fails.
 */
export declare const _eval: (input: unknown, expression: string) => any;
/**
 * Generates a new UUID (Universally Unique Identifier).
 *
 * @example
 * uuid() // "123e4567-e89b-12d3-a456-426614174000"
 * uuid() // "987fcdeb-51a2-43d7-b123-456789abcdef" (different each time)
 * @group Utility
 *
 * @returns A new UUID v4 string.
 */
export declare const uuid: () => string;
/**
 * Returns the type of the input value as a string.
 *
 * Supported return values:
 * - "string", "number", "boolean", "undefined", "array", "object"
 * - Only for JS: "function", "symbol", "bigint"
 *
 * @param input - The value to check the type of.
 * @returns {string} The type of the input value.
 *
 * @example
 * type(5); // "number"
 * foo|type; // "string"
 * type(true); // "boolean"
 * [1,2,3]|type; // "array"
 * {foo:1}|type; // "object"
 * undefined|type; // "undefined"
 */
export declare const getType: (input: unknown) => string;