rs-0.5.0 — Initial math package design#

This release introduces the first Marslang-written standard-library package and runtime numeric type tracking. The math package is an early, provisional design: more functionality will be added, and its API may evolve.

std.math#

takepkg std.math; provides math.min, math.max, math.abs, and math.clamp. Explicit aliases and storing functions in variables are supported. The algorithms are written in std/math.mars, compiled by Rust, and bundled into the generated JavaScript with the shared runtime.

takepkg std.math;
func m{
    out(math.clamp(12,0,10)); // 10
}

Arguments must have matching numeric types (int, longint, or finite float). Clamp includes both bounds and rejects reversed bounds. Integer overflow, incorrect argument counts, and invalid numeric arguments raise runtime errors. See the math API for details and current limits.

Dynamic typing and numeric behavior#

Unannotated variables can change type on reassignment. Annotated bindings retain runtime checks, and fixed still prevents reassignment. Numeric kinds survive function calls, returns, containers, family fields, and copies: 1.0 remains a float even when its value is integral. Numeric unions prefer the existing kind.

Arithmetic now uses runtime operand kinds, including through union-typed calls. Integer arithmetic checks overflow; float arithmetic retains float results. Mixed longint/float arithmetic requires an explicit conversion. Scalar equality and collection lookups retain their value-based numeric behavior. Fixed containers cannot have their numeric kinds changed through a differently annotated alias.

Migration: integer calculations that previously bypassed overflow checks through unannotated or union-typed values can now raise an error. Use longint or float explicitly when those numeric semantics are required. := remains excluded.

Repository and validation#

• .mars and .js.inc files are excluded from GitHub Linguist language detection.
• The public API reference documents the package and dynamic typing rules.
• cargo test passes 63 tests: 7 unit and 56 integration, none ignored, using WSL-native Rust with Windows Node. The toolchains use separate target directories.

Remaining work#

More math APIs, decimal/fraction support, full filesystem modules/exports, other standard packages, decorators, and self-hosting remain pending. Infinity/NaN math semantics are deferred; this initial package requires finite float inputs.