mirror of
https://github.com/samber/lo.git
synced 2026-04-22 23:47:11 +08:00
Samuel Berthe
90 lines
2.5 KiB
Go
90 lines
2.5 KiB
Go
//go:build go1.23
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package it
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import (
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"iter"
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"github.com/samber/lo"
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)
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// ToSeqPtr returns a sequence of pointers to each value.
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// Play: https://go.dev/play/p/Z9nA8cC3dXw
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func ToSeqPtr[T any](collection iter.Seq[T]) iter.Seq[*T] {
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return Map(collection, lo.ToPtr)
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}
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// FromSeqPtr returns a sequence with the pointer values.
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// Returns a zero value in case of a nil pointer element.
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// Play: https://go.dev/play/p/A1bB9dD4eYx
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func FromSeqPtr[T any](collection iter.Seq[*T]) iter.Seq[T] {
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return Map(collection, lo.FromPtr)
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}
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// FromSeqPtrOr returns a sequence with the pointer values or the fallback value.
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// Play: https://go.dev/play/p/B2cC8eE5fYz
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func FromSeqPtrOr[T any](collection iter.Seq[*T], fallback T) iter.Seq[T] {
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return Map(collection, func(x *T) T { return lo.FromPtrOr(x, fallback) })
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}
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// ToAnySeq returns a sequence with all elements mapped to `any` type.
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// Play: https://go.dev/play/p/C3dD9fF6Za1
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func ToAnySeq[T any](collection iter.Seq[T]) iter.Seq[any] {
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return Map(collection, func(x T) any { return x })
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}
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// FromAnySeq returns a sequence with all elements mapped to a type.
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// Panics on type conversion failure.
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// Play: https://go.dev/play/p/D4eE0gG7Ab2
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func FromAnySeq[T any](collection iter.Seq[any]) iter.Seq[T] {
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return Map(collection, func(item any) T {
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if t, ok := item.(T); ok {
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return t
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}
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panic("it.FromAnySeq: type conversion failed")
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})
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}
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// Empty returns an empty sequence.
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// Play: https://go.dev/play/p/E5fF1hH8Bc3
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func Empty[T any]() iter.Seq[T] {
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return func(yield func(T) bool) {}
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}
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// IsEmpty returns true if the sequence is empty.
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// Will iterate at most once.
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// Play: https://go.dev/play/p/F6gG2iI9Cd4
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func IsEmpty[T any](collection iter.Seq[T]) bool {
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for range collection {
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return false
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}
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return true
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}
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// IsNotEmpty returns true if the sequence is not empty.
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// Will iterate at most once.
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// Play: https://go.dev/play/p/G7hH3jJ0De5
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func IsNotEmpty[T any](collection iter.Seq[T]) bool {
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return !IsEmpty(collection)
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}
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// CoalesceSeq returns the first non-empty sequence.
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// Will iterate through each sub-sequence at most once.
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// Play: https://go.dev/play/p/H8iI4kK1Ef6
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func CoalesceSeq[T any](v ...iter.Seq[T]) (iter.Seq[T], bool) {
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for i := range v {
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for range v[i] {
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return v[i], true
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}
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}
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return Empty[T](), false
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}
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// CoalesceSeqOrEmpty returns the first non-empty sequence.
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// Will iterate through each sub-sequence at most once.
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// Play: https://go.dev/play/p/I9jJ5lL2Fg7
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func CoalesceSeqOrEmpty[T any](v ...iter.Seq[T]) iter.Seq[T] {
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result, _ := CoalesceSeq(v...)
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return result
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}
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