56 lines
936 B
Go
56 lines
936 B
Go
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package rangex
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import (
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"github.com/mojosa-software/godat/src/iterx"
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cnts "golang.org/x/exp/constraints"
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)
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type Range[V cnts.Ordered] struct {
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start, step, end V
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}
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// Returns the new Range strucucture with corresponding start, step and end.
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// If the values can never reach the end then the function will return nil.
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func New[V cnts.Ordered](start, step, end V) *Range[V] {
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return &Range[V]{
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start, step, end,
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}
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}
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func (r *Range[V]) Chan() iterx.PairChan[int, V] {
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start, step, end := r.start, r.step, r.end
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c := make(iterx.PairChan[int, V])
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go func(){
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var compare func(a, b V) bool
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less := func(a, b V) bool {
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return a < b
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}
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more := func(a, b V) bool {
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return a > b
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}
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if start < end {
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compare = less
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} else {
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compare = more
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}
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j := 0
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for i := start ; compare(i, end) ; i += step {
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c <- iterx.Pair[int, V]{
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K:j,
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V:i,
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}
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j++
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}
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close(c)
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}()
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return c
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}
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