composable_timer 0.1.0

Composable function timer that uses Kleisli compositing

composable_timer

Composable function timer that uses Kleisli composition

Motivation

Pretty often functions need to be timed. Not less often, those time measurements need to have some label or description with them.

This package provides set of helpers to do such a thing in a pure, boilerplate-free way using Monadic computation. But fear not! It is a very trivial application of such term and using this package is very straight-forward.

Getting started

Down are listed all possible timing variations with examples.

Single function timing

For simple single-function measurement, the ComposableTimer.run(...) function is used.

B fn(A input) => input.toB();

final input = A();
final timedToA = ComposableTimer.run('A to B conversion', () => fn(input));

timedToA variable will has a type TimedExecution<B>. This class holds three values:

• value – input function's obtained value.
• log – formatted measurement description, it this case, A to B conversion time: %number% milliseconds
• duration – Duration object that tells how much time it took

Timing composition

Usually, function timing is composed in some way. The ComposableTimer package provides three ways of composition.

Fish

ComposableTimer.fish(...) composes two timed functions and returns another function with fused outputs. Intended for functions that already return a TimedExecution<T>. The most simplest form of timer composition.

B fn1(A input) => input.toB();

C fn2(B input) => input.toC();

final composedFunction = ComposableTimer.fish(
  (A a) => ComposableTimer.run('A to B', () => fn1(a)),
  (B b) => ComposableTimer.run('B to C', () => fn2(b)),
);

The resulting function would take argument of type A and return a FutureOr<TimedExecution<C>>.

Fish Timing

ComposableTimer.fishTiming(...) composes two regular functions that were not intended to be timed and return regular values.

B fn1(A input) => input.toB();

C fn2(B input) => input.toC();

final composedFunction = ComposableTimer.fishTiming(
  TimerInput(fn1, 'A to B'),
  TimerInput(fn2, 'B to C'),
);

Fish Mixed

ComposableTimer.fishMixed(...) is a combination of the two previous functions. It allows composing non-timer functions further, while having the fisTiming(...) API.

B fn1(A input) => input.toB();

C fn2(B input) => input.toC();

X fn3(C input) => input.toX();

final composedFunction = ComposableTimer.fishMixed(
  ComposableTimer.fishTiming(
    TimerInput(fn1, 'A to B'),
    TimerInput(fn2, 'B to C'),
  ),
  TimerInput(fn3, 'C to X'),
);