50 lines
1.5 KiB
Go
50 lines
1.5 KiB
Go
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package stack
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import (
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"errors"
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)
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//Item is an interface which represents object that can be placed on the stack
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type Item interface {
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Integer() (*Int, error)
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Boolean() (*Boolean, error)
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ByteArray() (*ByteArray, error)
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Array() (*Array, error)
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Context() (*Context, error)
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}
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// Represents an `abstract` stack item
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// which will hold default values for stack items
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// this is intended to be embedded into types that you will use on the stack
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type abstractItem struct{}
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// Integer is the default implementation for a stackItem
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// Implements Item interface
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func (a *abstractItem) Integer() (*Int, error) {
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return nil, errors.New("This stack item is not an Integer")
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}
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// Boolean is the default implementation for a stackItem
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// Implements Item interface
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func (a *abstractItem) Boolean() (*Boolean, error) {
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return nil, errors.New("This stack item is not a Boolean")
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}
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// ByteArray is the default implementation for a stackItem
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// Implements Item interface
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func (a *abstractItem) ByteArray() (*ByteArray, error) {
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return nil, errors.New("This stack item is not a byte array")
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}
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// Array is the default implementation for a stackItem
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// Implements Item interface
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func (a *abstractItem) Array() (*Array, error) {
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return nil, errors.New("This stack item is not an array")
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}
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// Context is the default implementation for a stackItem
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// Implements Item interface
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func (a *abstractItem) Context() (*Context, error) {
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return nil, errors.New("This stack item is not of type context")
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}
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