feat: promise support for drops, working on #65

src/template/filter/filter.ts

@@ -19,9 +19,13 @@ export class Filter {
     this.impl = impl || (x => x)
     this.args = args
   }
-  render (value: any, scope: Scope): any {
-    const args = this.args.map(arg => isArray(arg) ? [arg[0], evalValue(arg[1], scope)] : evalValue(arg, scope))
-    return this.impl.apply(null, [value, ...args])
+  async render (value: any, scope: Scope) {
+    const argv: any[] = []
+    for(let arg of this.args) {
+      if (isArray(arg)) argv.push([arg[0], await evalValue(arg[1], scope)])
+      else argv.push(await evalValue(arg, scope))
+    }
+    return this.impl.apply(null, [value, ...argv])
   }
   static register (name: string, filter: FilterImpl) {
     Filter.impls[name] = filter

src/template/tag/hash.ts

@@ -10,13 +10,15 @@ import Scope from '../../scope/scope'
  */
 export default class Hash {
   [key: string]: any
-  constructor (markup: string, scope: Scope) {
+  static async create (markup: string, scope: Scope) {
+    const instance = new Hash()
     let match
     hashCapture.lastIndex = 0
     while ((match = hashCapture.exec(markup))) {
       const k = match[1]
       const v = match[2]
-      this[k] = evalValue(v, scope)
+      instance[k] = await evalValue(v, scope)
     }
+    return instance
   }
 }

src/template/tag/tag.ts

@@ -28,7 +28,7 @@ export default class Tag extends Template<TagToken> implements ITemplate {
     }
   }
   async render (scope: Scope) {
-    const hash = new Hash(this.token.args, scope)
+    const hash = await Hash.create(this.token.args, scope)
     const impl = this.impl
     if (typeof impl.render !== 'function') {
       return ''

src/template/value.ts

@@ -47,10 +47,12 @@ export default class Value {
     }
     this.filters.push(new Filter(name, args, this.strictFilters))
   }
-  value (scope: Scope) {
-    return this.filters.reduce(
-      (prev, filter) => filter.render(prev, scope),
-      evalExp(this.initial, scope))
+  async value (scope: Scope) {
+    let val = await evalExp(this.initial, scope)
+    for (let filter of this.filters) {
+      val = await filter.render(val, scope)
+    }
+    return val
   }
   static tokenize (str: string): Array<'|' | ',' | ':' | string> {
     const tokens = []