Add mod, a remainder that is never negative - #54
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Stiven-Gjekaj merged 2 commits intoAug 24, 2026
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% truncates toward zero, so -7 % 3 is -1. That stays put under the stability guarantee. Wrapping uses (ring buffers, clocks, board edges) want the floored form instead. mod(n, d) is that form: the sign follows the divisor, a zero divisor refuses with the same words % uses, and floats match because % already accepts them. Fixes Stiven-Gjekaj#44 Signed-off-by: Vedant Madane <6527493+VedantMadane@users.noreply.github.com>
Record the builtin in section 8.7, bump the pinned counts, and note the wrapping cases next to the other math functions. Signed-off-by: Vedant Madane <6527493+VedantMadane@users.noreply.github.com>
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Summary
Adds
mod(n, d), a floored remainder builtin.%keeps truncating toward zero (section 5 / stability);modis the wrapping form every ring buffer and clock face wants.Behaviour
mod(-1, 10)9mod(-7, 3)2mod(7, 3)1(same as%)mod(1, -10)-9(sign follows divisor)mod(1, 0)modulo by zero(same words as%)a - d * floor(a/d)).Touches
src/builtins.rs— register, implement, unit tests,BUILTIN_NAMES, kind countstests/golden.rs— pinned cases for negatives, floats, zero divisorTests
cargo test --workspacegreen (MSVC)cargo clippy --all-targets -- -D warningsgreencargo fmt --all --checkgreenFixes #44