time.round-to-increment

pub fn round_to_increment(minutes: i64, increment: i64, mode: &str) -> i64

fune!(time.round-to-increment@^1);  // then call round_to_increment(…)

use super::funejson::Value;  ← the fune runtime: the JSON value the test vectors use; fune build keeps it only where a signature takes one
use super::math_round_div::round_div;  ← from math.round-div ^1.0.0 · built alongside by fune

/// Round a duration to a whole number of billing increments. The rounding is
/// math.round-div's, so "half-up" here is the same rule as for money.
///
/// # Panics
/// Panics on negative minutes, an increment below one, or an unknown mode.
pub fn round_to_increment(minutes: i64, increment: i64, mode: &str) -> i64 {
    if minutes < 0 {
        panic!("minutes must be a non-negative integer, received {}", minutes);
    }
    if increment < 1 {
        panic!("increment must be a positive integer, received {}", increment);
    }
    round_div(minutes, increment, mode) * increment
}

pub fn fune_vector(args: &[Value]) -> Value {
    Value::Int(round_to_increment(
        args[0].as_i64(),
        args[1].as_i64(),
        args[2].as_str(),
    ))
}

Install

fune build

With that line in your source, in a Rust project (language rust in fune.project), fune build resolves it and its 1 dependency, pins them in fune.lock, downloads only the Rust package of each, and builds the code above into your project’s .fune/build, one readable file per capability with a header linking back here. A crate’s build.rs runs it before every compile. Or pin a range in fune.project and build in one step:

fune add time.round-to-increment

The manifest, vectors and README with only the Rust implementation. Install it without the registry with fune add ./time.round-to-increment-1.0.0-rust.fune, or fetch it from a terminal with fune pull time.round-to-increment@1.0.0:rust.

The whole function, every language, is one file too: time.round-to-increment-1.0.0.fune, 7,541 bytes, sha256 a025300b5b63a666a8089af6172507925276781f65c341183991b49c65834fc8. It installs into a project of any language.

// fune: before time.round-to-increment

// fune: after time.round-to-increment

// fune: replace math.round-div in time.round-to-increment

// fune: step time.round-to-increment after <n|label>

More from the author

- `up`: any part of a unit bills as a whole one. The usual rule for professional time. - `down`: only completed units count. - `half-up`: nearest unit, a tie (exactly half a unit) goes up. This is "nearest". - `half-even`: nearest unit, a tie goes to the even number of units, so ties do not bias a long timesheet upwards.

Rounding applies to the one duration you pass. Round each entry and then add, or add and then round, but know which your terms of business say: seven 3-minute calls rounded up in six-minute units bill 42 minutes one way and 24 the other.

Zero stays zero in every mode. A minimum charge ("at least one unit per call") is a business rule on top of this, not rounding. Durations are never negative; minutes below zero and an increment below one are errors.

Files