Split grammar (#15)

* Move grammar parsers to entity classes

* Fix includes

* Fix Entity5 test

* Small detail

* Fix unknown keys entities

* Persistent grammar objects

* Fix grammar

* Grammar from variable

js/entity/UnknownPinEntity.js

@@ -1,8 +1,31 @@
+import Parsimmon from "parsimmon"
 import PinEntity from "./PinEntity.js"
+import Grammar from "../serialization/Grammar.js"
 
 export default class UnknownPinEntity extends PinEntity {
 
     static lookbehind = ""
+    static grammar = this.createGrammar()
+
+    static createGrammar() {
+        return Parsimmon.lazy(() => Parsimmon.seq(
+            Grammar.regexMap(
+                new RegExp(`${Grammar.Regex.Symbol.source}\\s*\\(\\s*`),
+                result => result[1] ?? ""
+            ),
+            Grammar.createAttributeGrammar(this).sepBy1(Grammar.commaSeparation),
+            Parsimmon.regex(/\s*(?:,\s*)?\)/)
+        )
+            .map(([lookbehind, attributes, _2]) => {
+                let values = {}
+                if (lookbehind.length) {
+                    values.lookbehind = lookbehind
+                }
+                attributes.forEach(attributeSetter => attributeSetter(values))
+                return new this(values)
+            })
+        )
+    }
 
     constructor(values = {}) {
         super(values, true)