module Steppable

Overview

Implements a #step method for iterating from a value.

steppable.cr

Instance Method Detail

def step(*, to limit = nil, by step, exclusive : Bool = false, &) : Nil #

Iterates from self to limit incrementing by the amount of step on each iteration. If exclusive is true, limit is excluded from the iteration.

ary = [] of Int32
1.step(to: 4, by: 2) do |x|
ary << x
end
ary                                        # => [1, 3]
1.step(to: 4, by: 2).to_a                  # => [1, 3]
1.step(to: 4, by: 1).to_a                  # => [1, 2, 3, 4]
1.step(to: 4, by: 1, exclusive: true).to_a # => [1, 2, 3]

The type of each iterated element is typeof(self + step).

If to is nil, iteration is open ended.

The starting point (self) is always iterated as first element, with two exceptions:

• if self and to don't compare (i.e. (self <=> to).nil?). Example: 1.0.step(Float::NAN)
• if the direction of to differs from the direction of by. Example: 1.step(to: 2, by: -1)

In those cases the iteration is empty.

def step(*, to limit = nil, by step, exclusive : Bool = false) #

Iterates from self to limit incrementing by the amount of step on each iteration. If exclusive is true, limit is excluded from the iteration.

ary = [] of Int32
1.step(to: 4, by: 2) do |x|
ary << x
end
ary                                        # => [1, 3]
1.step(to: 4, by: 2).to_a                  # => [1, 3]
1.step(to: 4, by: 1).to_a                  # => [1, 2, 3, 4]
1.step(to: 4, by: 1, exclusive: true).to_a # => [1, 2, 3]

The type of each iterated element is typeof(self + step).

If to is nil, iteration is open ended.

The starting point (self) is always iterated as first element, with two exceptions:

• if self and to don't compare (i.e. (self <=> to).nil?). Example: 1.0.step(Float::NAN)
• if the direction of to differs from the direction of by. Example: 1.step(to: 2, by: -1)

In those cases the iteration is empty.