forked from lix-project/lix-website
52 lines
849 B
JavaScript
52 lines
849 B
JavaScript
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
|