65 lines
1.7 KiB
Go
65 lines
1.7 KiB
Go
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/*
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AMU: Custom simple markup language
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Copyright (C) 2021 Arsen Musayelyan
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This program is free software: you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation, either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <https://www.gnu.org/licenses/>.
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*/
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// Package stack implements a simple stack using go slices.
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package stack
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import "reflect"
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// Stack is a LIFO stack using slices for storage
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type Stack struct {
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items []interface{}
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}
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// Create a new stack
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func New() *Stack {
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return &Stack{}
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}
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// Add a value to the end of the stack
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func (s *Stack) Push(val interface{}) {
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// Add element to slice
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s.items = append(s.items, val)
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}
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// Remove the value on the end of the stack and return it.
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func (s *Stack) Pop() interface{} {
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// Get index of last element
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n := s.Size() - 1
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// Get last item in slice
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item := s.items[n]
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// Set element to zero value
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s.items[n] = reflect.Zero(reflect.TypeOf(item)).Interface()
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// Remove element
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s.items = s.items[:n]
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return item
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}
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// Return value on the end of the stack without removing
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func (s *Stack) Peek() interface{} {
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// Get index of last element
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n := s.Size() - 1
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// Return last element
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return s.items[n]
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}
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// Get the amount of items on the stack
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func (s *Stack) Size() int {
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return len(s.items)
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}
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