27 lines
480 B
Go
27 lines
480 B
Go
package internal
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import (
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"sync"
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)
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type memoizedFunc[T any] struct {
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once sync.Once
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fn func() (T, error)
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result T
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err error
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}
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func (mf *memoizedFunc[T]) do() (T, error) {
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mf.once.Do(func() {
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mf.result, mf.err = mf.fn()
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})
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return mf.result, mf.err
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}
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// Memoize the result of a function call.
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//
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// fn is only ever called once, even if it returns an error.
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func Memoize[T any](fn func() (T, error)) func() (T, error) {
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return (&memoizedFunc[T]{fn: fn}).do
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}
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