module VirtualTime::Search

Overview

Search provides monotonic, DST-safe, policy-free temporal traversal suitable for scheduling. Stateless. Not related to other methods above. Advances by at least 1 step before evaluation.

Defined in:

virtualtime.cr

Class Method Summary

.shift_from_base(base : Time, step : Time::Span, *, domain : Domain | Nil = nil, max_shift : Time::Span | Nil = nil, max_shifts : Int32 | Nil = nil, &blocked : Time -> Bool) : Result::Result
Moves forward from base by repeated application of step (successor behavior: first candidate is base + step).
.shifted_from_base?(target : Time, step : Time::Span, *, max_shift : Time::Span | Nil = nil, max_shifts : Int32, &producer : Time -> Time::Span | Nil) : Bool
Inverse reachability check: determine backwards whether target can be obtained as base + delta, stepping by step.

Class Method Detail

def self.shift_from_base(base : Time, step : Time::Span, *, domain : Domain | Nil = nil, max_shift : Time::Span | Nil = nil, max_shifts : Int32 | Nil = nil, &blocked : Time -> Bool) : Result::Result #

Moves forward from base by repeated application of step (successor behavior: first candidate is base + step).

Returns:

Result::Found holding the Time::Span delta to the first unblocked candidate
Result::Blocked if max_shifts is exhausted before a candidate is accepted
Result::OutOfBounds if max_shift or domain is exceeded
Result::InvalidStep if step is zero

Notes:

step must be non-zero
max_shift bounds the returned delta (inclusive)
max_shifts bounds the number of step applications (inclusive)
stepping is done on Time values (DST-safe)
the search is only as bounded as its arguments: if domain, max_shift, and max_shifts are all nil and every candidate is blocked, it never returns. Supply at least one bound unless the block is certain to eventually accept a candidate.

[View source]

def self.shifted_from_base?(target : Time, step : Time::Span, *, max_shift : Time::Span | Nil = nil, max_shifts : Int32, &producer : Time -> Time::Span | Nil) : Bool #

Inverse reachability check: determine backwards whether target can be obtained as base + delta, stepping by step. Returns bool value.