Methods & Static Namespaces

Since beta.13, most operations on values use method syntax: value.method(args). Methods are resolved at runtime based on the value’s type tag. Each type has its own set of methods.

Achronyme also provides static namespaces using Type::MEMBER syntax for type-level constants and constructors.

Method Syntax

// Method call
let items = [3, 1, 2]
let sorted = items.sort(fn(a, b) { a - b })

// Chaining
let result = [1, 2, 3, 4, 5]
    .filter(fn(n) { n > 2 })
    .map(fn(n) { n * 10 })
// result: [30, 40, 50]

Note

Maps can store closures as fields. If a map field has the same name as a built-in method, the prototype method takes priority. The closure is used as fallback only when no built-in method exists for that name.

---

Int

6 methods on integer values.

.abs()

Returns the absolute value.

let x = -42
assert(x.abs() == 42)

.min(other)

Returns the smaller of two integers.

assert(3.min(7) == 3)

.max(other)

Returns the larger of two integers.

assert(3.max(7) == 7)

.pow(exp)

Integer exponentiation. Exponent must be non-negative.

assert(2.pow(10) == 1024)

.to_field()

Converts the integer to a BN254 field element.

let f = 42.to_field()
assert(typeof(f) == "Field")

.to_string()

Returns the string representation.

assert(42.to_string() == "42")

Static: Int::MAX, Int::MIN

60-bit signed integer bounds.

print(Int::MAX)  // 576460752303423487 (2^59 - 1)
print(Int::MIN)  // -576460752303423488 (-2^59)

---

String

14 methods on string values.

.len()

Returns the character count.

assert("hello".len() == 5)

.starts_with(prefix)

Returns true if the string starts with the given prefix.

assert("hello".starts_with("hel"))

.ends_with(suffix)

Returns true if the string ends with the given suffix.

assert("hello".ends_with("llo"))

.contains(substr)

Returns true if the string contains the substring.

assert("hello world".contains("world"))

.split(delimiter)

Splits the string by the given delimiter. Returns a list of strings.

assert("a,b,c".split(",") == ["a", "b", "c"])

.trim()

Removes leading and trailing whitespace.

assert("  hello  ".trim() == "hello")

.replace(search, replacement)

Replaces all occurrences of search with replacement.

assert("aabbcc".replace("bb", "XX") == "aaXXcc")

.to_upper()

Converts all characters to uppercase.

assert("hello".to_upper() == "HELLO")

.to_lower()

Converts all characters to lowercase.

assert("HELLO".to_lower() == "hello")

.chars()

Splits into a list of individual characters.

assert("abc".chars() == ["a", "b", "c"])

.index_of(substr)

Returns the character index of the first occurrence. Returns -1 if not found.

assert("hello world".index_of("world") == 6)
assert("hello".index_of("xyz") == -1)

.substring(start, end)

Extracts a substring from position start to end (exclusive). Indices are clamped to string bounds.

assert("hello".substring(1, 4) == "ell")

.repeat(n)

Repeats the string n times. Maximum result size is 10 MB.

assert("ab".repeat(3) == "ababab")

.to_string()

Returns the string itself (identity).

assert("hi".to_string() == "hi")

---

List

13 methods on list values.

.len()

Returns the element count.

assert([1, 2, 3].len() == 3)

.push(item)

Appends an item to the end. Mutates the list in-place. Returns nil.

mut items = [1, 2]
items.push(3)
assert(items.len() == 3)

.pop()

Removes and returns the last element. Returns nil if empty.

mut items = [1, 2, 3]
assert(items.pop() == 3)
assert(items.len() == 2)

.map(fn)

Returns a new list with fn(elem) applied to each element.

let doubled = [1, 2, 3].map(fn(n) { n * 2 })
assert(doubled == [2, 4, 6])

.filter(fn)

Returns a new list containing only elements where fn(elem) is truthy.

let evens = [1, 2, 3, 4].filter(fn(n) { n % 2 == 0 })
assert(evens == [2, 4])

.reduce(initial, fn)

Folds the list into a single value: acc = fn(acc, elem) for each element.

let sum = [1, 2, 3].reduce(0, fn(acc, n) { acc + n })
assert(sum == 6)

.for_each(fn)

Calls fn(elem) for each element (for side effects). Returns nil.

[1, 2, 3].for_each(fn(n) { print(n) })

.find(fn)

Returns the first element where fn(elem) is truthy, or nil if none match.

let found = [1, 2, 3, 4].find(fn(n) { n > 2 })
assert(found == 3)

.any(fn)

Returns true if fn(elem) is truthy for any element. Short-circuits.

assert([1, 2, 3].any(fn(n) { n == 2 }))

.all(fn)

Returns true if fn(elem) is truthy for all elements. Short-circuits.

assert([1, 2, 3].all(fn(n) { n > 0 }))

.sort(fn)

Returns a new sorted list. The comparator fn(a, b) must return negative if a < b, zero if equal, positive if a > b.

let sorted = [3, 1, 2].sort(fn(a, b) { a - b })
assert(sorted == [1, 2, 3])

.flat_map(fn)

Like .map(), but flattens one level of nested lists.

let result = [1, 2, 3].flat_map(fn(n) { [n, n * 10] })
assert(result == [1, 10, 2, 20, 3, 30])

.zip(other)

Returns a list of [a, b] pairs, truncated to the shorter list.

let pairs = [1, 2, 3].zip([10, 20, 30])
assert(pairs == [[1, 10], [2, 20], [3, 30]])

---

Map

8 methods on map values.

.len()

Returns the number of key-value pairs.

let m = {name: "Alice", age: 30}
assert(m.len() == 2)

.keys()

Returns a list of all keys.

let m = {name: "Alice", age: 30}
let k = m.keys()
assert(k.len() == 2)

.values()

Returns a list of all values.

let m = {a: 1, b: 2, c: 3}
let v = m.values()
assert(v.len() == 3)

.entries()

Returns a list of [key, value] pairs.

let m = {x: 10, y: 20}
let e = m.entries()
// e contains [["x", 10], ["y", 20]]
assert(e.len() == 2)

.contains_key(key)

Returns true if the map contains the given key.

let m = {name: "Alice"}
assert(m.contains_key("name"))
assert(!m.contains_key("age"))

.get(key, default)

Returns the value for key, or default if the key doesn’t exist.

let m = {name: "Alice"}
assert(m.get("name", "?") == "Alice")
assert(m.get("age", 0) == 0)

.set(key, value)

Sets or updates a key-value pair. Mutates the map in-place. Returns nil.

mut m = {}
m.set("name", "Alice")
m.set("age", 30)
assert(m.len() == 2)
assert(m.name == "Alice")

.remove(key)

Removes a key and returns its value. Returns nil if the key doesn’t exist.

mut m = {name: "Alice", age: 30}
let removed = m.remove("age")
assert(removed == 30)
assert(m.len() == 1)

---

Field

2 methods on BN254 field elements.

.to_int()

Converts the field element to an integer. The value must fit in 64 bits.

let f = 0p42
assert(f.to_int() == 42)

.to_string()

Returns the decimal string representation.

let f = 0p42
assert(f.to_string() == "42")

Static: Field::ZERO, Field::ONE, Field::ORDER

Field constants for BN254 Fr.

let z = Field::ZERO   // 0p0
let o = Field::ONE     // 0p1
let q = Field::ORDER   // "21888242871839275222246405745257275088548364400416034343698204186575808495617"

---

BigInt

7 methods on BigInt256 and BigInt512 values.

.to_bits()

Converts to a list of 0/1 integers in LSB-first order. Length is 256 or 512 depending on width.

let bits = bigint256(42).to_bits()
// bits[0] = 0, bits[1] = 1, bits[2] = 0, bits[3] = 1, bits[4] = 0, bits[5] = 1

.bit_and(other)

Bitwise AND. Both operands must have the same width.

let result = bigint256("0xFF").bit_and(bigint256("0x0F"))
assert(result == bigint256("0x0F"))

.bit_or(other)

Bitwise OR. Both operands must have the same width.

let result = bigint256("0xF0").bit_or(bigint256("0x0F"))
assert(result == bigint256("0xFF"))

.bit_xor(other)

Bitwise XOR. Both operands must have the same width.

let result = bigint256("0xFF").bit_xor(bigint256("0x0F"))
assert(result == bigint256("0xF0"))

.bit_not()

Bitwise NOT (flips all bits).

let x = bigint256(0).bit_not()  // all bits set

.bit_shl(n)

Shifts left by n bits. Errors if any set bits are shifted out (overflow).

assert(bigint256(1).bit_shl(8) == bigint256(256))

.bit_shr(n)

Shifts right by n bits. Bits shifted out are discarded.

assert(bigint256(256).bit_shr(8) == bigint256(1))

Static: BigInt::from_bits

Alias for the global from_bits function.

let val = BigInt::from_bits(bigint256(42).to_bits(), 256)
assert(val == bigint256(42))

---

Summary Table

Methods by Type

Type	Method	Args	Returns
Int	.abs()	0	Int
	.min(other)	1	Int
	.max(other)	1	Int
	.pow(exp)	1	Int
	.to_field()	0	Field
	.to_string()	0	String
String	.len()	0	Int
	.starts_with(prefix)	1	Bool
	.ends_with(suffix)	1	Bool
	.contains(substr)	1	Bool
	.split(delim)	1	List
	.trim()	0	String
	.replace(search, repl)	2	String
	.to_upper()	0	String
	.to_lower()	0	String
	.chars()	0	List
	.index_of(substr)	1	Int
	.substring(start, end)	2	String
	.repeat(n)	1	String
	.to_string()	0	String
List	.len()	0	Int
	.push(item)	1	nil
	.pop()	0	value
	.map(fn)	1	List
	.filter(fn)	1	List
	.reduce(init, fn)	2	value
	.for_each(fn)	1	nil
	.find(fn)	1	value
	.any(fn)	1	Bool
	.all(fn)	1	Bool
	.sort(fn)	1	List
	.flat_map(fn)	1	List
	.zip(other)	1	List
Map	.len()	0	Int
	.keys()	0	List
	.values()	0	List
	.entries()	0	List
	.contains_key(key)	1	Bool
	.get(key, default)	2	value
	.set(key, value)	2	nil
	.remove(key)	1	value
Field	.to_int()	0	Int
	.to_string()	0	String
BigInt	.to_bits()	0	List
	.bit_and(other)	1	BigInt
	.bit_or(other)	1	BigInt
	.bit_xor(other)	1	BigInt
	.bit_not()	0	BigInt
	.bit_shl(n)	1	BigInt
	.bit_shr(n)	1	BigInt

Static Namespaces

Namespace	Member	Value
Int::MAX		576460752303423487 (2^59 - 1)
Int::MIN		-576460752303423488 (-2^59)
Field::ZERO		Field element 0
Field::ONE		Field element 1
Field::ORDER		BN254 Fr modulus (string)
BigInt::from_bits		from_bits(bits, width) constructor