32 lines
1.4 KiB
Go
32 lines
1.4 KiB
Go
/*
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Package iterator provides functions to work with Neo iterators.
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*/
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package iterator
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import "github.com/tutus-one/tutus-chain/pkg/interop/tutusinternal"
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// Iterator represents a Neo iterator, it's an opaque data structure that can
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// be properly created by storage.Find. Iterators range over key-value pairs,
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// so it's convenient to use them for maps. This structure is similar in
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// function to Neo .net framework's Iterator.
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type Iterator struct{}
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// Next advances the iterator returning true if it was successful (and you
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// can use Value to get value for slices or key-value pair for maps) and false
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// otherwise (and there are no more elements in this Iterator). This function
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// uses `System.Iterator.Next` syscall.
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func Next(it Iterator) bool {
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return tutusinternal.Syscall1("System.Iterator.Next", it).(bool)
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}
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// Value returns iterator's current value. It's only valid to call after
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// a successful Next call. This function uses `System.Iterator.Value` syscall.
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// For slices, the result is just value.
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// For maps, the result can be cast to a slice of 2 elements: a key and a value.
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// For storage iterators, refer to `storage.FindFlags` documentation.
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// If the iterator is configured to return key-value pairs, the result can be
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// directly type-asserted to [storage.KeyValue] type.
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func Value(it Iterator) any {
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return tutusinternal.Syscall1("System.Iterator.Value", it)
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}
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