DeciMojo v0.4.1

01/07/2025 (v0.4.1)

Version 0.4.1 of DeciMojo introduces implicit type conversion between built-in integral types and arbitrary-precision types.

⭐️ New

Now DeciMojo supports implicit type conversion between built-in integeral types (Int, UInt, Int8, UInt8, Int16, UInt16, Int32, UInt32, Int64, UInt64, Int128,UInt128, Int256, and UInt256) and the arbitrary-precision types (BigUInt, BigInt, and BigDecimal). This allows you to use these built-in types directly in arithmetic operations with BigInt and BigUInt without explicit conversion. The merged type will always be the most compatible one (PR #89, PR #90).

For example, you can now do the following:

from decimojo.prelude import *

fn main() raises:
    var a = BInt(Int256(-1234567890))
    var b = BigUInt(31415926)
    var c = BDec("3.14159265358979323")

    print("a =", a)
    print("b =", b)
    print("c =", c)

    print(a * b)  # Merged to BInt
    print(a + c)  # Merged to BDec
    print(b + c)  # Merged to BDec
    print(a * Int(-128))  # Merged to BInt
    print(b * UInt(8))  # Merged to BUInt
    print(c * Int256(987654321123456789))  # Merged to BDec

    var lst = [a, b, c, UInt8(255), Int64(22222), UInt256(1234567890)]
    # The list is of the type `List[BigDecimal]`
    for i in lst:
        print(i, end=", ")

Running the code will give your the following results:

a = -1234567890
b = 31415926
c = 3.14159265358979323
-38785093474216140
-1234567886.85840734641020677
31415929.14159265358979323
158024689920
251327408
3102807559527666386.46423202534973847
-1234567890, 31415926, 3.14159265358979323, 255, 22222, 1234567890,

🦋 Changed

Optimize the case when you increase the value of a BigInt object in-place by 1, i.e., i += 1. This allows you to iterate faster (PR #89). For example, we can compute the time taken to iterate from 0 to 1_000_000 using BigInt and compare it with the built-in Int type:

from decimojo.prelude import *

fn main() raises:
    i = BigInt(0)
    end = BigInt(1_000_000)
    while i < end:
        print(i)
        i += 1

scenario	Time taken
v0.4.0 BigInt	1.102s
v0.4.1 BigInt	0.912s
Built-in Int	0.893s

🛠️ Fixed

Fix a bug in BigDecimal where it cannot create a correct value from a integral scalar, e.g., BDec(UInt16(0)) returns an unitialized BigDecimal object (PR #89).

📚 Documentation and testing

Update the tests module and refactor the test files for BigUInt (PR #88).

What's Changed

• [integer][tests] Add operation overload between BigInt and Int + refactor some tests by @forfudan in #88
• [integer][decimal] Allows implicit type conversion and type merging by @forfudan in #89
• [integer][decimal][docs] Improve type conversions + optimize iadd for BigInt + Update documentation by @forfudan in #90

Full Changelog: v0.4.0...v0.4.1