feat: with & for in render tag, closes #195

src/render/expression.ts

@@ -4,14 +4,15 @@ import { Value } from './value'
 import { Context } from '../context/context'
 import { toValue } from '../util/underscore'
 import { isOperator, precedence, operatorImpls } from './operator'
-import { tokenize } from '../parser/expression-tokenizer'
+import { Tokenizer } from '../parser/tokenizer'
 
 export class Expression {
   private operands: any[] = []
   private postfix: string[]
 
   public constructor (str = '') {
-    this.postfix = [...toPostfix(tokenize(str))]
+    const tokenizer = new Tokenizer(str)
+    this.postfix = [...toPostfix(tokenizer.readExpression())]
   }
   public * evaluate (ctx: Context) {
     assert(ctx, 'unable to evaluate: context not defined')

src/render/operator.ts

@@ -52,8 +52,6 @@ export const operatorImpls: {[key: string]: (lhs: any, rhs: any) => boolean} = {
   'or': (l: any, r: any) => isTruthy(l) || isTruthy(r)
 }
 
-const list = Object.keys(precedence)
-
 export function isOperator (token: string) {
-  return list.includes(token)
+  return precedence.hasOwnProperty(token)
 }

src/render/range.ts

@@ -3,8 +3,8 @@ import { Context } from '../context/context'
 import { range } from '../util/underscore'
 import { Value } from './value'
 
-export function isRange (token: string) {
-  return token[0] === '(' && token[token.length - 1] === ')'
+export function isRange (str: string) {
+  return rangeLine.test(str)
 }
 
 export function * rangeValue (token: string, ctx: Context) {