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46 lines
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1,003 B
Markdown
46 lines
No EOL
1,003 B
Markdown
# Set
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A set represents a collection, which is structurally a duplicate, unordered array.
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```python
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assert Set.from([1, 2, 3, 2, 1]) == {1, 2, 3}
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assert {1, 2} == {1, 1, 2} # duplicates are automatically removed
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assert {1, 2} == {2, 1}
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```
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Sets can perform set operations.
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```python
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assert 1 in {1, 2, 3}
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assert not 1 in {}
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assert {1} or {2} == {1, 2}
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assert {1, 2} and {2, 3} == {2}
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assert {1, 2} not {2} == {1}
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```
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A set is a homogeneous collection. In order for objects of different classes to coexist, they must be homogenized.
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```python
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s: {Int or Str} = {"a", 1, "b", -1}
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```
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## Sets as types
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Sets can also be treated as types. Such types are called __Enum types__.
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```python
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i: {1, 2, 3} = 1
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assert i in {1, 2, 3}
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```
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Elements of the set are directly elements of the type.
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Note that the sets themselves are different.
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```python
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mut_set = {1, 2, 3}.into {Int; !3}
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mut_set.insert!(4)
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```
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<p align='center'>
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<a href='./13_record.md'>Previous</a> | <a href='./15_type.md'>Next</a>
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</p> |