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Diffstat (limited to 'vendor/github.com/emirpasic/gods/containers/iterator.go')
-rw-r--r-- | vendor/github.com/emirpasic/gods/containers/iterator.go | 109 |
1 files changed, 109 insertions, 0 deletions
diff --git a/vendor/github.com/emirpasic/gods/containers/iterator.go b/vendor/github.com/emirpasic/gods/containers/iterator.go new file mode 100644 index 0000000000..f1a52a365a --- /dev/null +++ b/vendor/github.com/emirpasic/gods/containers/iterator.go @@ -0,0 +1,109 @@ +// Copyright (c) 2015, Emir Pasic. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package containers + +// IteratorWithIndex is stateful iterator for ordered containers whose values can be fetched by an index. +type IteratorWithIndex interface { + // Next moves the iterator to the next element and returns true if there was a next element in the container. + // If Next() returns true, then next element's index and value can be retrieved by Index() and Value(). + // If Next() was called for the first time, then it will point the iterator to the first element if it exists. + // Modifies the state of the iterator. + Next() bool + + // Value returns the current element's value. + // Does not modify the state of the iterator. + Value() interface{} + + // Index returns the current element's index. + // Does not modify the state of the iterator. + Index() int + + // Begin resets the iterator to its initial state (one-before-first) + // Call Next() to fetch the first element if any. + Begin() + + // First moves the iterator to the first element and returns true if there was a first element in the container. + // If First() returns true, then first element's index and value can be retrieved by Index() and Value(). + // Modifies the state of the iterator. + First() bool +} + +// IteratorWithKey is a stateful iterator for ordered containers whose elements are key value pairs. +type IteratorWithKey interface { + // Next moves the iterator to the next element and returns true if there was a next element in the container. + // If Next() returns true, then next element's key and value can be retrieved by Key() and Value(). + // If Next() was called for the first time, then it will point the iterator to the first element if it exists. + // Modifies the state of the iterator. + Next() bool + + // Value returns the current element's value. + // Does not modify the state of the iterator. + Value() interface{} + + // Key returns the current element's key. + // Does not modify the state of the iterator. + Key() interface{} + + // Begin resets the iterator to its initial state (one-before-first) + // Call Next() to fetch the first element if any. + Begin() + + // First moves the iterator to the first element and returns true if there was a first element in the container. + // If First() returns true, then first element's key and value can be retrieved by Key() and Value(). + // Modifies the state of the iterator. + First() bool +} + +// ReverseIteratorWithIndex is stateful iterator for ordered containers whose values can be fetched by an index. +// +// Essentially it is the same as IteratorWithIndex, but provides additional: +// +// Prev() function to enable traversal in reverse +// +// Last() function to move the iterator to the last element. +// +// End() function to move the iterator past the last element (one-past-the-end). +type ReverseIteratorWithIndex interface { + // Prev moves the iterator to the previous element and returns true if there was a previous element in the container. + // If Prev() returns true, then previous element's index and value can be retrieved by Index() and Value(). + // Modifies the state of the iterator. + Prev() bool + + // End moves the iterator past the last element (one-past-the-end). + // Call Prev() to fetch the last element if any. + End() + + // Last moves the iterator to the last element and returns true if there was a last element in the container. + // If Last() returns true, then last element's index and value can be retrieved by Index() and Value(). + // Modifies the state of the iterator. + Last() bool + + IteratorWithIndex +} + +// ReverseIteratorWithKey is a stateful iterator for ordered containers whose elements are key value pairs. +// +// Essentially it is the same as IteratorWithKey, but provides additional: +// +// Prev() function to enable traversal in reverse +// +// Last() function to move the iterator to the last element. +type ReverseIteratorWithKey interface { + // Prev moves the iterator to the previous element and returns true if there was a previous element in the container. + // If Prev() returns true, then previous element's key and value can be retrieved by Key() and Value(). + // Modifies the state of the iterator. + Prev() bool + + // End moves the iterator past the last element (one-past-the-end). + // Call Prev() to fetch the last element if any. + End() + + // Last moves the iterator to the last element and returns true if there was a last element in the container. + // If Last() returns true, then last element's key and value can be retrieved by Key() and Value(). + // Modifies the state of the iterator. + Last() bool + + IteratorWithKey +} |