58 lines
1.7 KiB
Go
58 lines
1.7 KiB
Go
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package erratum
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import "io"
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// These are the support types and interface definitions used in the
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// implementation if your Use function. See the test suite file at
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// for information on the expected implementation.
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//
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// Because this is part of the package "erratum", if your solution file
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// is also declared in the package you will automatically have access to
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// these definitions (you do not have to re-declare them).
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// TransientError is an error that may occur while opening a resource via
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// ResourceOpener.
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type TransientError struct {
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err error
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}
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func (e TransientError) Error() string {
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return e.err.Error()
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}
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// FrobError is a possible error from doing some frobbing, your implementation
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// will require calling your Resource's Defrob(string) method.
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// When this error occurs, the FrobError's defrobTag string will contain the
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// string you must pass into Defrob.
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type FrobError struct {
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defrobTag string
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inner error
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}
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func (e FrobError) Error() string {
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return e.inner.Error()
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}
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type Resource interface {
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// Resource is using composition to inherit the requirements of the io.Closer
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// interface. What this means is that a Resource will have a .Close() method.
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io.Closer
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// Frob does something with the input string.
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// Because this is an incredibly badly designed system if there is an error
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// it panics.
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//
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// The paniced error may be a FrobError in which case Defrob should be called
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// with the defrobTag string.
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Frob(string)
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Defrob(string)
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}
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// ResourceOpener is a function that creates a resource.
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//
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// It may return a wrapped error of type TransientError. In this case the resource
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// is temporarily unavailable and the caller should retry soon.
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type ResourceOpener func() (Resource, error)
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