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package lo
// Ternary is a 1 line if/else statement.
// Play: https://go.dev/play/p/t-D7WBL44h2
func Ternary[T any](condition bool, ifOutput T, elseOutput T) T {
if condition {
return ifOutput
}
return elseOutput
}
// TernaryF is a 1 line if/else statement whose options are functions
// Play: https://go.dev/play/p/AO4VW20JoqM
func TernaryF[T any](condition bool, ifFunc func() T, elseFunc func() T) T {
if condition {
return ifFunc()
}
return elseFunc()
}
type ifElse[T any] struct {
result T
done bool
}
// If.
// Play: https://go.dev/play/p/WSw3ApMxhyW
func If[T any](condition bool, result T) *ifElse[T] {
if condition {
return &ifElse[T]{result, true}
}
var t T
return &ifElse[T]{t, false}
}
// IfF.
// Play: https://go.dev/play/p/WSw3ApMxhyW
func IfF[T any](condition bool, resultF func() T) *ifElse[T] {
if condition {
return &ifElse[T]{resultF(), true}
}
var t T
return &ifElse[T]{t, false}
}
// ElseIf.
// Play: https://go.dev/play/p/WSw3ApMxhyW
func (i *ifElse[T]) ElseIf(condition bool, result T) *ifElse[T] {
if !i.done && condition {
i.result = result
i.done = true
}
return i
}
// ElseIfF.
// Play: https://go.dev/play/p/WSw3ApMxhyW
func (i *ifElse[T]) ElseIfF(condition bool, resultF func() T) *ifElse[T] {
if !i.done && condition {
i.result = resultF()
i.done = true
}
return i
}
// Else.
// Play: https://go.dev/play/p/WSw3ApMxhyW
func (i *ifElse[T]) Else(result T) T {
if i.done {
return i.result
}
return result
}
// ElseF.
// Play: https://go.dev/play/p/WSw3ApMxhyW
func (i *ifElse[T]) ElseF(resultF func() T) T {
if i.done {
return i.result
}
return resultF()
}
type switchCase[T comparable, R any] struct {
predicate T
result R
done bool
}
// Switch is a pure functional switch/case/default statement.
// Play: https://go.dev/play/p/TGbKUMAeRUd
func Switch[T comparable, R any](predicate T) *switchCase[T, R] {
var result R
return &switchCase[T, R]{
predicate,
result,
false,
}
}
// Case.
// Play: https://go.dev/play/p/TGbKUMAeRUd
func (s *switchCase[T, R]) Case(val T, result R) *switchCase[T, R] {
if !s.done && s.predicate == val {
s.result = result
s.done = true
}
return s
}
// CaseF.
// Play: https://go.dev/play/p/TGbKUMAeRUd
func (s *switchCase[T, R]) CaseF(val T, cb func() R) *switchCase[T, R] {
if !s.done && s.predicate == val {
s.result = cb()
s.done = true
}
return s
}
// Default.
// Play: https://go.dev/play/p/TGbKUMAeRUd
func (s *switchCase[T, R]) Default(result R) R {
if !s.done {
s.result = result
}
return s.result
}
// DefaultF.
// Play: https://go.dev/play/p/TGbKUMAeRUd
func (s *switchCase[T, R]) DefaultF(cb func() R) R {
if !s.done {
s.result = cb()
}
return s.result
}
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