mirror of
https://github.com/mickael-menu/zk
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29 lines
583 B
Go
29 lines
583 B
Go
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package core
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// lazyStringer implements Stringer and wait for String() to be called the first
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// time before computing its value.
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type lazyStringer struct {
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value *string
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render func() string
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}
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func newLazyStringer(render func() string) *lazyStringer {
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return &lazyStringer{render: render}
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}
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// String implements Stringer.
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func (s *lazyStringer) String() string {
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if s == nil {
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return ""
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}
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if s.value == nil {
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str := s.render()
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s.value = &str
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}
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return *s.value
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}
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func (s *lazyStringer) MarshalJSON() ([]byte, error) {
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return []byte(`"` + s.String() + `"`), nil
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}
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