26 lines
395 B
Go
26 lines
395 B
Go
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package main
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import (
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"context"
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"fmt"
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)
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func main() {
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type favContextKey string
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f := func(ctx context.Context, k favContextKey) {
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if v := ctx.Value(k); v != nil {
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fmt.Println("found value:", v)
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return
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}
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fmt.Println("key not found:", k)
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}
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k := favContextKey("language")
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ctx := context.WithValue(context.Background(), k, "Go")
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f(ctx, k)
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f(ctx, favContextKey("color"))
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}
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