37 lines
554 B
Go
37 lines
554 B
Go
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package memento
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// Command ...
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type Command interface {
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Execute()
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Undo()
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}
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type commands []Command
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// Memento ...
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type Memento struct {
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stack []commands
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cmds commands
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}
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// Execute ...
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func (m *Memento) Execute(cmd Command) {
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m.cmds = append(m.cmds, cmd)
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cmd.Execute()
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}
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// Commit ...
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func (m *Memento) Commit() {
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m.stack = append(m.stack, m.cmds)
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m.cmds = nil
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}
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// Rollback ...
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func (m *Memento) Rollback() {
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cmds := m.stack[len(m.stack)-1]
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m.stack = m.stack[:len(m.stack)-1]
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for i := len(cmds) - 1; i >= 0; i-- {
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cmds[i].Undo()
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}
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}
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