refactor(all): remove unneeded getters/setters and obsolete code

Remove unneeded getters/setters.
Remove old dccdgroup code.
Remove unneeded code from watch record.
Improving code paragraphing.
Fixing linting errors.

Author: EisenbergEffect

src/ast.js

@@ -14,7 +14,10 @@ function _argsList(list) {
 
 export class AST {
   constructor(expression) {
-    if (typeof expression !== "string") throw "expression must be a string";
+    if (typeof expression !== "string") {
+      throw "expression must be a string";
+    }
+
     this.expression = expression.indexOf('#.') === 0
                     ? expression.substr(2)
                     : expression;
@@ -43,10 +46,14 @@ export class ContextReferenceAST extends AST {
 
 export class ConstantAST extends AST {
   constructor(constant, expression) {
-    if (arguments.length < 2) expression = null;
+    if (arguments.length < 2) {
+      expression = null;
+    }
+
     super(expression === null
         ? (typeof constant === "string" ? `"${constant}"` : `${constant}`)
         : expression);
+
     this.constant = constant;
   }
 
@@ -59,6 +66,7 @@ export class FieldReadAST extends AST {
   constructor(lhs, name) {
     this.lhs = lhs;
     this.name = name;
+
     super(`${lhs}.${name}`);
   }
 
@@ -72,6 +80,7 @@ export class PureFunctionAST extends AST {
     this.fn = fn;
     this.argsAST = argsAST;
     this.name = name;
+
     super(`${name}(${_argsList(argsAST)})`);
   }
 
@@ -85,6 +94,7 @@ export class MethodAST extends AST {
     this.lhsAST = lhsAST;
     this.name = name;
     this.argsAST = argsAST;
+
     super(`${lhsAST}.${name}(${_argsList(argsAST)})`);
   }
 
@@ -96,6 +106,7 @@ export class MethodAST extends AST {
 export class CollectionAST extends AST {
   constructor(valueAST) {
     this.valueAST = valueAST;
+
     super(`#collection(${valueAST})`);
   }
 
@@ -108,6 +119,7 @@ class _ConstantWatchRecord {
   constructor(watchGroup, expression, currentValue) {
     this.currentValue = currentValue;
     this.handler = new _ConstantHandler(watchGroup, expression, currentValue);
+    this.field = this.previousValue = this.object = this.nextChange = null;
   }
 
   check() {
@@ -117,24 +129,4 @@ class _ConstantWatchRecord {
   remove() {
     return null;
   }
-
-  get field() {
-    return null;
-  }
-
-  get previousValue() {
-    return null;
-  }
-
-  get object() {
-    return null;
-  }
-
-  set object(value) {
-    return null;
-  }
-
-  get nextChange() {
-    return null;
-  }
 }