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rest

rest(iter, state)

An iterator that yields the same elements as iter, but starting at the given state.

Examples

1. Generate the rest of an iterator starting from a given state:

   julia> iter = Iterators.cycle([1, 2, 3]);
   julia> rest_iter = rest(iter, 2);
   julia> collect(take(rest_iter, 5))
   5-element Array{Int64,1}:
   2
   3
   1
   2
   3

   In this example, we create an iterator iter that cycles through the elements [1, 2, 3]. We then generate a new iterator rest_iter using rest, starting from the state 2. We collect the first 5 elements from rest_iter using take and store them in an array.

2. Start from a different state in a range:

   julia> range_iter = Iterators.range(1, step=2, length=10);
   julia> rest_iter = rest(range_iter, 3);
   julia> collect(take(rest_iter, 5))
   5-element Array{Int64,1}:
   5
   7
   9
   11
   13

   In this example, we create a range iterator range_iter starting from 1, with a step of 2, and a length of 10. We generate a new iterator rest_iter using rest, starting from the state 3. We collect the first 5 elements from rest_iter using take and store them in an array.

3. Use with custom iterator types:

   julia> struct MyIterator
             state::Int
         end
   julia> Base.iterate(itr::MyIterator, state) = state > 0 ? (state, state-1) : nothing
   julia> iter = MyIterator(5);
   julia> rest_iter = rest(iter, 2);
   julia> collect(take(rest_iter, 5))
   5-element Array{Int64,1}:
   2
   1
   0

   Here, we define a custom iterator type MyIterator that counts down from a given state. We implement the iterate method for this iterator. We create an instance of MyIterator with an initial state of 5. We then generate a new iterator rest_iter using rest, starting from the state 2. We collect the first 5 elements from rest_iter using take and store them in an array.

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