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var Mexp = require('./postfix.js')
Mexp.prototype.postfixEval = function (UserDefined) {
'use strict'
UserDefined = UserDefined || {}
UserDefined.PI = Math.PI
UserDefined.E = Math.E
var stack = [],
pop1,
pop2,
pop3
var disp = []
var temp = ''
var arr = this.value
var bool = typeof UserDefined.n !== 'undefined'
for (var i = 0; i < arr.length; i++) {
if (arr[i].type === 1) {
stack.push({ value: arr[i].value, type: 1 })
} else if (arr[i].type === 3) {
stack.push({ value: UserDefined[arr[i].value], type: 1 })
} else if (arr[i].type === 0) {
if (typeof stack[stack.length - 1].type === 'undefined') {
stack[stack.length - 1].value.push(arr[i])
} else stack[stack.length - 1].value = arr[i].value(stack[stack.length - 1].value)
} else if (arr[i].type === 7) {
if (typeof stack[stack.length - 1].type === 'undefined') {
stack[stack.length - 1].value.push(arr[i])
} else stack[stack.length - 1].value = arr[i].value(stack[stack.length - 1].value)
} else if (arr[i].type === 8) {
var popped = []
for (var x = 0; x < arr[i].numberOfArguments; x++) {
popped.push(stack.pop().value)
}
stack.push({ type: 1, value: arr[i].value.apply(arr[i], popped.reverse()) })
} else if (arr[i].type === 10) {
pop1 = stack.pop()
pop2 = stack.pop()
if (typeof pop2.type === 'undefined') {
pop2.value = pop2.concat(pop1)
pop2.value.push(arr[i])
stack.push(pop2)
} else if (typeof pop1.type === 'undefined') {
pop1.unshift(pop2)
pop1.push(arr[i])
stack.push(pop1)
} else {
stack.push({ type: 1, value: arr[i].value(pop2.value, pop1.value) })
}
} else if (arr[i].type === 2 || arr[i].type === 9) {
pop1 = stack.pop()
pop2 = stack.pop()
if (typeof pop2.type === 'undefined') {
pop2 = pop2.concat(pop1)
pop2.push(arr[i])
stack.push(pop2)
} else if (typeof pop1.type === 'undefined') {
pop1.unshift(pop2)
pop1.push(arr[i])
stack.push(pop1)
} else {
stack.push({ type: 1, value: arr[i].value(pop2.value, pop1.value) })
}
} else if (arr[i].type === 12) {
pop1 = stack.pop()
if (typeof pop1.type !== 'undefined') {
pop1 = [pop1]
}
pop2 = stack.pop()
pop3 = stack.pop()
stack.push({ type: 1, value: arr[i].value(pop3.value, pop2.value, new Mexp(pop1)) })
} else if (arr[i].type === 13) {
if (bool) {
stack.push({ value: UserDefined[arr[i].value], type: 3 })
} else stack.push([arr[i]])
}
}
if (stack.length > 1) {
throw new Mexp.Exception('Uncaught Syntax error')
}
return stack[0].value > 1000000000000000 ? 'Infinity' : parseFloat(stack[0].value.toFixed(15))
}
Mexp.eval = function (str, tokens, obj) {
if (typeof tokens === 'undefined') {
return this.lex(str).toPostfix().postfixEval()
} else if (typeof obj === 'undefined') {
if (typeof tokens.length !== 'undefined') return this.lex(str, tokens).toPostfix().postfixEval()
else return this.lex(str).toPostfix().postfixEval(tokens)
} else return this.lex(str, tokens).toPostfix().postfixEval(obj)
}
module.exports = Mexp
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