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| function last(array) {
| return array[array.length - 1]
| }
|
| let brackets = {
| /**
| * Parse string to nodes tree
| */
| parse(str) {
| let current = ['']
| let stack = [current]
|
| for (let sym of str) {
| if (sym === '(') {
| current = ['']
| last(stack).push(current)
| stack.push(current)
| continue
| }
|
| if (sym === ')') {
| stack.pop()
| current = last(stack)
| current.push('')
| continue
| }
|
| current[current.length - 1] += sym
| }
|
| return stack[0]
| },
|
| /**
| * Generate output string by nodes tree
| */
| stringify(ast) {
| let result = ''
| for (let i of ast) {
| if (typeof i === 'object') {
| result += `(${brackets.stringify(i)})`
| continue
| }
|
| result += i
| }
| return result
| }
| }
|
| module.exports = brackets
|
|
