diff --git a/app/imports/api/engine/computation/buildComputation/linkCalculationDependencies.js b/app/imports/api/engine/computation/buildComputation/linkCalculationDependencies.js
index 69f747ee..0e91f833 100644
--- a/app/imports/api/engine/computation/buildComputation/linkCalculationDependencies.js
+++ b/app/imports/api/engine/computation/buildComputation/linkCalculationDependencies.js
@@ -1,6 +1,5 @@
-import SymbolNode from '/imports/parser/parseTree/SymbolNode.js';
-import AccessorNode from '/imports/parser/parseTree/AccessorNode.js';
 import findAncestorByType from '/imports/api/engine/computation/utility/findAncestorByType.js';
+import { traverse } from '/imports/parser/resolve.js';
 
 export default function linkCalculationDependencies(dependencyGraph, prop, {propsById}){
   prop._computationDetails.calculations.forEach(calcObj => {
@@ -9,9 +8,9 @@ export default function linkCalculationDependencies(dependencyGraph, prop, {prop
       // ancestors: {} //this gets added if there are resolved ancestors
     };
     // Traverse the parsed calculation looking for variable names
-    calcObj._parsedCalculation.traverse(node => {
+    traverse(calcObj._parsedCalculation, node => {
       // Skip nodes that aren't symbols or accessors
-      if (!(node instanceof SymbolNode || node instanceof AccessorNode)) return;
+      if (node.parseType !== 'symbol' && node.parseType !== 'accessor') return;
       // Link ancestor references as direct property dependencies
       if (node.name[0] === '#'){
         let ancestorProp = getAncestorProp(
diff --git a/app/imports/api/engine/computation/buildComputation/parseCalculationFields.js b/app/imports/api/engine/computation/buildComputation/parseCalculationFields.js
index 72e698f3..1d824e85 100644
--- a/app/imports/api/engine/computation/buildComputation/parseCalculationFields.js
+++ b/app/imports/api/engine/computation/buildComputation/parseCalculationFields.js
@@ -1,8 +1,8 @@
 import INLINE_CALCULATION_REGEX from '/imports/constants/INLINE_CALCULTION_REGEX.js';
 import { prettifyParseError, parse } from '/imports/parser/parser.js';
-import ErrorNode from '/imports/parser/parseTree/ErrorNode.js';
 import applyFnToKey from '/imports/api/engine/computation/utility/applyFnToKey.js';
-import { get, unset } from 'lodash';
+import { get } from 'lodash';
+import errorNode from '/imports/parser/parseTree/error.js'
 
 export default function parseCalculationFields(prop, schemas){
   discoverInlineCalculationFields(prop, schemas);
@@ -66,6 +66,6 @@ function parseCalculation(calcObj){
     calcObj.errors ?
       calcObj.errors.push(error) :
       calcObj.errors = [error];
-    calcObj._parsedCalculation = new ErrorNode({error});
+    calcObj._parsedCalculation = errorNode.create({error});
   }
 }
diff --git a/app/imports/api/engine/computation/computeComputation/computeCalculations.js b/app/imports/api/engine/computation/computeComputation/computeCalculations.js
index 4034b5eb..ccbaf79f 100644
--- a/app/imports/api/engine/computation/computeComputation/computeCalculations.js
+++ b/app/imports/api/engine/computation/computeComputation/computeCalculations.js
@@ -1,7 +1,5 @@
-import { CompilationContext } from '/imports/parser/parser.js';
+import resolve, { toString } from '/imports/parser/resolve.js';
 import INLINE_CALCULATION_REGEX from '/imports/constants/INLINE_CALCULTION_REGEX.js';
-import ConstantNode from '/imports/parser/parseTree/ConstantNode.js';
-import ErrorNode from '/imports/parser/parseTree/ErrorNode.js';
 
 export default function computeCalculations(computation, node){
   if (!node.data) return;
@@ -15,17 +13,16 @@ export default function computeCalculations(computation, node){
 }
 
 function evaluateCalculation(calculation, scope){
-  const context = new CompilationContext();
   const parseNode = calculation._parsedCalculation;
   const fn = calculation._parseLevel;
   const calculationScope = {...calculation._localScope, ...scope};
-  const resultNode = parseNode[fn](calculationScope, context);
-  if (resultNode instanceof ConstantNode){
+  const {result: resultNode, context} = resolve(fn, parseNode, calculationScope);
+  if (resultNode.parseType === 'constant'){
     calculation.value = resultNode.value;
-  } else if (resultNode instanceof ErrorNode){
+  } else if (resultNode.parseType === 'error'){
     calculation.value = null;
   } else {
-    calculation.value = resultNode.toString();
+    calculation.value = toString(resultNode);
   }
   if (calculation.errors){
     calculation.errors = [...calculation.errors, ...context.errors]
diff --git a/app/imports/api/properties/Constants.js b/app/imports/api/properties/Constants.js
index 4b1f382f..0995ccd9 100644
--- a/app/imports/api/properties/Constants.js
+++ b/app/imports/api/properties/Constants.js
@@ -3,12 +3,10 @@ import VARIABLE_NAME_REGEX from '/imports/constants/VARIABLE_NAME_REGEX.js';
 import ErrorSchema from '/imports/api/properties/subSchemas/ErrorSchema.js';
 import {
   parse,
-  CompilationContext,
   prettifyParseError,
 } from '/imports/parser/parser.js';
-import AccessorNode from '/imports/parser/parseTree/AccessorNode.js';
-import SymbolNode from '/imports/parser/parseTree/SymbolNode.js';
 import STORAGE_LIMITS from '/imports/constants/STORAGE_LIMITS.js';
+import resolve, { Context, traverse } from '/imports/parser/resolve.js';
 
 /*
  * Constants are primitive values that can be used elsewhere in computations
@@ -50,12 +48,9 @@ let ConstantSchema = new SimpleSchema({
       // Any existing errors will result in an early failure
       if (context && context.errors.length) return context.errors;
       // Ban variables in constants if necessary
-      result && result.traverse(node => {
-        if (node instanceof SymbolNode || node instanceof AccessorNode){
-          context.storeError({
-            type: 'error',
-            message: 'Variables can\'t be used to define a constant'
-          });
+      result && traverse(result, node => {
+        if (node.parseType === 'symbol' || node.parseType === 'accessor'){
+          context.error('Variables can\'t be used to define a constant');
         }
       });
       return context && context.errors || [];
@@ -67,7 +62,7 @@ let ConstantSchema = new SimpleSchema({
 });
 
 function parseString(string, fn = 'compile'){
-  let context = new CompilationContext();
+  let context = new Context();
   if (!string){
     return {result: string, context};
   }
@@ -78,10 +73,11 @@ function parseString(string, fn = 'compile'){
     node = parse(string);
   } catch (e) {
     let message = prettifyParseError(e);
-    context.storeError({type: 'error', message});
+    context.error(message);
     return {context};
   }
-  let result = node[fn]({/*empty scope*/}, context);
+  if (!node) return {context};
+  let {result} = resolve(fn, node, {/*empty scope*/}, context);
   return {result, context}
 }
 
diff --git a/app/imports/parser/ResolveContext.js b/app/imports/parser/ResolveContext.js
deleted file mode 100644
index 3edd2fa8..00000000
--- a/app/imports/parser/ResolveContext.js
+++ /dev/null
@@ -1,20 +0,0 @@
-export default class Context {
-  constructor({errors = [], rolls = []}){
-    this.errors = errors;
-    this.rolls = rolls;
-  }
-  error(e){
-    if (!e) return;
-    if (typeof e === 'string'){
-      this.errors.push({
-        type: 'error',
-        message: e,
-      });
-    } else {
-      this.errors.push(e);
-    }
-  }
-  roll(r){
-    this.rolls.push(r);
-  }
-}
diff --git a/app/imports/parser/TextField.vue b/app/imports/parser/TextField.vue
new file mode 100644
index 00000000..9c9f0919
--- /dev/null
+++ b/app/imports/parser/TextField.vue
@@ -0,0 +1,38 @@
+<template lang="html">
+  <v-text-field
+    ref="input"
+    v-bind="$attrs"
+    class="dc-text-field"
+    :loading="loading"
+    :error-messages="errors"
+    :value="safeValue"
+    :disabled="isDisabled"
+    :outlined="!regular"
+    @input="input"
+    @focus="focused = true"
+    @blur="focused = false"
+    @keyup="e => $emit('keyup', e)"
+  >
+    <template #append>
+      <slot name="value" />
+    </template>
+  </v-text-field>
+</template>
+
+<script lang="js">
+  import SmartInput from '/imports/ui/components/global/SmartInputMixin.js';
+
+  export default {
+    mixins: [SmartInput],
+    props: {
+      regular: Boolean,
+    },
+  };
+</script>
+
+<style lang="css">
+.dc-text-field .v-input__append-inner{
+  font-size: 12px;
+  margin-top: 36px;
+}
+</style>
diff --git a/app/imports/parser/functions.js b/app/imports/parser/functions.js
index b1ec5a91..9213665e 100644
--- a/app/imports/parser/functions.js
+++ b/app/imports/parser/functions.js
@@ -1,5 +1,3 @@
-import ArrayNode from '/imports/parser/parseTree/ArrayNode.js';
-
 export default {
   'abs': {
     comment: 'Returns the absolute value of a number',
@@ -101,7 +99,7 @@ export default {
       {input: 'tableLookup([100, 300, 900, 1200], 900)', result: '3'},
       {input: 'tableLookup([100, 300], 594)', result: '2'},
     ],
-    arguments: [ArrayNode, 'number'],
+    arguments: ['array', 'number'],
     resultType: 'number',
     fn: function tableLookup(arrayNode, number){
       for(let i in arrayNode.values){
diff --git a/app/imports/parser/grammar.js b/app/imports/parser/grammar.js
index 8e29fb16..064fc2f2 100644
--- a/app/imports/parser/grammar.js
+++ b/app/imports/parser/grammar.js
@@ -1,19 +1,8 @@
-// Generated automatically by nearley, version 2.16.0
+// Generated automatically by nearley, version 2.20.1
 // http://github.com/Hardmath123/nearley
 function id(x) { return x[0]; }
 
-  import AccessorNode from '/imports/parser/parseTree/AccessorNode.js';
-  import ArrayNode from '/imports/parser/parseTree/ArrayNode.js';
-	import CallNode from '/imports/parser/parseTree/CallNode.js';
-	import ConstantNode from '/imports/parser/parseTree/ConstantNode.js';
-  import IfNode from '/imports/parser/parseTree/IfNode.js';
-	import IndexNode from '/imports/parser/parseTree/IndexNode.js';
-	import OperatorNode from '/imports/parser/parseTree/OperatorNode.js';
-  import ParenthesisNode from '/imports/parser/parseTree/ParenthesisNode.js';
-  import RollNode from '/imports/parser/parseTree/RollNode.js';
-  import SymbolNode from '/imports/parser/parseTree/SymbolNode.js';
-  import UnaryOperatorNode from '/imports/parser/parseTree/UnaryOperatorNode.js';
-  import NotOperatorNode from '/imports/parser/parseTree/NotOperatorNode.js';
+  import node from './parseTree/_index.js';
 
 	import moo from 'moo';
 
@@ -53,7 +42,7 @@ function id(x) { return x[0]; }
 
   function nuller() { return null; }
   function operator([left, _1, operator, _2, right], fn){
-    return new OperatorNode({
+    return node.operator.create({
       left,
       right,
       operator: operator.value,
@@ -65,7 +54,7 @@ let ParserRules = [
     {"name": "spacedExpression", "symbols": ["_", "expression", "_"], "postprocess": d => d[1]},
     {"name": "expression", "symbols": ["ifStatement"], "postprocess": id},
     {"name": "ifStatement", "symbols": ["orExpression", "_", (lexer.has("ifOperator") ? {type: "ifOperator"} : ifOperator), "_", "orExpression", "_", (lexer.has("elseOperator") ? {type: "elseOperator"} : elseOperator), "_", "ifStatement"], "postprocess": 
-        d => new IfNode({condition: d[0], consequent: d[4], alternative: d[8]})
+        d => node.if.create({condition: d[0], consequent: d[4], alternative: d[8]})
           },
     {"name": "ifStatement", "symbols": ["orExpression"], "postprocess": id},
     {"name": "orExpression", "symbols": ["orExpression", "_", (lexer.has("orOperator") ? {type: "orOperator"} : orOperator), "_", "andExpression"], "postprocess": d => operator(d, 'or')},
@@ -82,18 +71,18 @@ let ParserRules = [
     {"name": "remainderExpression", "symbols": ["multiplicativeExpression"], "postprocess": id},
     {"name": "multiplicativeExpression", "symbols": ["multiplicativeExpression", "_", (lexer.has("multiplicativeOperator") ? {type: "multiplicativeOperator"} : multiplicativeOperator), "_", "rollExpression"], "postprocess": d => operator(d, 'multiply')},
     {"name": "multiplicativeExpression", "symbols": ["rollExpression"], "postprocess": id},
-    {"name": "rollExpression", "symbols": ["rollExpression", "_", (lexer.has("diceOperator") ? {type: "diceOperator"} : diceOperator), "_", "exponentExpression"], "postprocess": d => new RollNode({left: d[0], right: d[4]})},
+    {"name": "rollExpression", "symbols": ["rollExpression", "_", (lexer.has("diceOperator") ? {type: "diceOperator"} : diceOperator), "_", "exponentExpression"], "postprocess": d => node.roll.create({left: d[0], right: d[4]})},
     {"name": "rollExpression", "symbols": ["singleRollExpression"], "postprocess": id},
-    {"name": "singleRollExpression", "symbols": [{"literal":"d"}, "_", "singleRollExpression"], "postprocess": d => new RollNode({left: new ConstantNode({value: 1, type: 'number'}), right: d[2]})},
+    {"name": "singleRollExpression", "symbols": [{"literal":"d"}, "_", "singleRollExpression"], "postprocess": d => node.roll.create({left: node.constant.create({value: 1}), right: d[2]})},
     {"name": "singleRollExpression", "symbols": ["exponentExpression"], "postprocess": id},
     {"name": "exponentExpression", "symbols": ["callExpression", "_", (lexer.has("exponentOperator") ? {type: "exponentOperator"} : exponentOperator), "_", "exponentExpression"], "postprocess": d => operator(d, 'exponent')},
     {"name": "exponentExpression", "symbols": ["unaryExpression"], "postprocess": id},
-    {"name": "unaryExpression", "symbols": [(lexer.has("additiveOperator") ? {type: "additiveOperator"} : additiveOperator), "_", "unaryExpression"], "postprocess": d => new UnaryOperatorNode({operator: d[0].value, right: d[2]})},
+    {"name": "unaryExpression", "symbols": [(lexer.has("additiveOperator") ? {type: "additiveOperator"} : additiveOperator), "_", "unaryExpression"], "postprocess": d => node.unaryOperator.create({operator: d[0].value, right: d[2]})},
     {"name": "unaryExpression", "symbols": ["notExpression"], "postprocess": id},
-    {"name": "notExpression", "symbols": [(lexer.has("notOperator") ? {type: "notOperator"} : notOperator), "_", "notExpression"], "postprocess": d => new NotOperatorNode({right: d[2]})},
+    {"name": "notExpression", "symbols": [(lexer.has("notOperator") ? {type: "notOperator"} : notOperator), "_", "notExpression"], "postprocess": d => node.notOperator.create({right: d[2]})},
     {"name": "notExpression", "symbols": ["callExpression"], "postprocess": id},
     {"name": "callExpression", "symbols": ["name", "_", "arguments"], "postprocess": 
-        d => new CallNode ({functionName: d[0].name, args: d[2]})
+        d => node.call.create({functionName: d[0].name, args: d[2]})
           },
     {"name": "callExpression", "symbols": ["indexExpression"], "postprocess": id},
     {"name": "arguments$ebnf$1$subexpression$1", "symbols": ["expression"], "postprocess": d => d[0]},
@@ -105,7 +94,7 @@ let ParserRules = [
     {"name": "arguments", "symbols": [{"literal":"("}, "_", "arguments$ebnf$1", "arguments$ebnf$2", "_", {"literal":")"}], "postprocess": 
         d => [d[2], ...d[3]]
         },
-    {"name": "indexExpression", "symbols": ["arrayExpression", {"literal":"["}, "_", "expression", "_", {"literal":"]"}], "postprocess": d => new IndexNode ({array: d[0], index: d[3]})},
+    {"name": "indexExpression", "symbols": ["arrayExpression", {"literal":"["}, "_", "expression", "_", {"literal":"]"}], "postprocess": d => node.index.create({array: d[0], index: d[3]})},
     {"name": "indexExpression", "symbols": ["arrayExpression"], "postprocess": id},
     {"name": "arrayExpression$ebnf$1$subexpression$1", "symbols": ["expression"], "postprocess": d => d[0]},
     {"name": "arrayExpression$ebnf$1", "symbols": ["arrayExpression$ebnf$1$subexpression$1"], "postprocess": id},
@@ -114,10 +103,10 @@ let ParserRules = [
     {"name": "arrayExpression$ebnf$2$subexpression$1", "symbols": ["_", (lexer.has("separator") ? {type: "separator"} : separator), "_", "expression"], "postprocess": d => d[3]},
     {"name": "arrayExpression$ebnf$2", "symbols": ["arrayExpression$ebnf$2", "arrayExpression$ebnf$2$subexpression$1"], "postprocess": function arrpush(d) {return d[0].concat([d[1]]);}},
     {"name": "arrayExpression", "symbols": [{"literal":"["}, "_", "arrayExpression$ebnf$1", "arrayExpression$ebnf$2", "_", {"literal":"]"}], "postprocess": 
-        d => new ArrayNode({values: d[2] ? [d[2], ...d[3]] : []})
+        d => node.array.create({values: d[2] ? [d[2], ...d[3]] : []})
           },
     {"name": "arrayExpression", "symbols": ["parenthesizedExpression"], "postprocess": id},
-    {"name": "parenthesizedExpression", "symbols": [{"literal":"("}, "_", "expression", "_", {"literal":")"}], "postprocess": d => new ParenthesisNode({content: d[2]})},
+    {"name": "parenthesizedExpression", "symbols": [{"literal":"("}, "_", "expression", "_", {"literal":")"}], "postprocess": d => node.parenthesis.create({content: d[2]})},
     {"name": "parenthesizedExpression", "symbols": ["accessorExpression"], "postprocess": id},
     {"name": "accessorExpression$subexpression$1", "symbols": [(lexer.has("name") ? {type: "name"} : name)], "postprocess": d => d[0].value},
     {"name": "accessorExpression$ebnf$1$subexpression$1", "symbols": [{"literal":"."}, (lexer.has("name") ? {type: "name"} : name)], "postprocess": d => d[1].value},
@@ -125,18 +114,18 @@ let ParserRules = [
     {"name": "accessorExpression$ebnf$1$subexpression$2", "symbols": [{"literal":"."}, (lexer.has("name") ? {type: "name"} : name)], "postprocess": d => d[1].value},
     {"name": "accessorExpression$ebnf$1", "symbols": ["accessorExpression$ebnf$1", "accessorExpression$ebnf$1$subexpression$2"], "postprocess": function arrpush(d) {return d[0].concat([d[1]]);}},
     {"name": "accessorExpression", "symbols": ["accessorExpression$subexpression$1", "accessorExpression$ebnf$1"], "postprocess": 
-        d=> new AccessorNode({name: d[0], path: d[1]})
+        d=> node.accessor.create({name: d[0], path: d[1]})
           },
     {"name": "accessorExpression", "symbols": ["valueExpression"], "postprocess": id},
     {"name": "valueExpression", "symbols": ["name"], "postprocess": id},
     {"name": "valueExpression", "symbols": ["number"], "postprocess": id},
     {"name": "valueExpression", "symbols": ["string"], "postprocess": id},
     {"name": "valueExpression", "symbols": ["boolean"], "postprocess": id},
-    {"name": "number", "symbols": [(lexer.has("number") ? {type: "number"} : number)], "postprocess": d => new ConstantNode({value: +d[0].value, type: 'number'})},
-    {"name": "name", "symbols": [(lexer.has("name") ? {type: "name"} : name)], "postprocess": d => new SymbolNode({name: d[0].value})},
-    {"name": "string", "symbols": [(lexer.has("string") ? {type: "string"} : string)], "postprocess": d => new ConstantNode({value: d[0].value, type: 'string'})},
-    {"name": "boolean", "symbols": [{"literal":"true"}], "postprocess": d => new ConstantNode({value: true, type: 'boolean'})},
-    {"name": "boolean", "symbols": [{"literal":"false"}], "postprocess": d => new ConstantNode({value: false, type: 'boolean'})},
+    {"name": "number", "symbols": [(lexer.has("number") ? {type: "number"} : number)], "postprocess": d => node.constant.create({value: +d[0].value})},
+    {"name": "name", "symbols": [(lexer.has("name") ? {type: "name"} : name)], "postprocess": d => node.symbol.create({name: d[0].value})},
+    {"name": "string", "symbols": [(lexer.has("string") ? {type: "string"} : string)], "postprocess": d => node.constant.create({value: d[0].value})},
+    {"name": "boolean", "symbols": [{"literal":"true"}], "postprocess": d => node.constant.create({value: true})},
+    {"name": "boolean", "symbols": [{"literal":"false"}], "postprocess": d => node.constant.create({value: false})},
     {"name": "_", "symbols": []},
     {"name": "_", "symbols": [(lexer.has("space") ? {type: "space"} : space)], "postprocess": nuller}
 ];
diff --git a/app/imports/parser/grammar.ne b/app/imports/parser/grammar.ne
index cd278bab..82681659 100644
--- a/app/imports/parser/grammar.ne
+++ b/app/imports/parser/grammar.ne
@@ -1,17 +1,6 @@
 @preprocessor esmodule
 @{%
-  import AccessorNode from '/imports/parser/parseTree/AccessorNode.js';
-  import ArrayNode from '/imports/parser/parseTree/ArrayNode.js';
-	import CallNode from '/imports/parser/parseTree/CallNode.js';
-	import ConstantNode from '/imports/parser/parseTree/ConstantNode.js';
-  import IfNode from '/imports/parser/parseTree/IfNode.js';
-	import IndexNode from '/imports/parser/parseTree/IndexNode.js';
-	import OperatorNode from '/imports/parser/parseTree/OperatorNode.js';
-  import ParenthesisNode from '/imports/parser/parseTree/ParenthesisNode.js';
-  import RollNode from '/imports/parser/parseTree/RollNode.js';
-  import SymbolNode from '/imports/parser/parseTree/SymbolNode.js';
-  import UnaryOperatorNode from '/imports/parser/parseTree/UnaryOperatorNode.js';
-  import NotOperatorNode from '/imports/parser/parseTree/NotOperatorNode.js';
+  import node from './parseTree/_index.js';
 
 	import moo from 'moo';
 
@@ -51,7 +40,7 @@
 
   function nuller() { return null; }
   function operator([left, _1, operator, _2, right], fn){
-    return new OperatorNode({
+    return node.operator.create({
       left,
       right,
       operator: operator.value,
@@ -71,7 +60,7 @@ expression ->
 
 ifStatement ->
   orExpression _ %ifOperator _ orExpression _ %elseOperator _ ifStatement {%
-     d => new IfNode({condition: d[0], consequent: d[4], alternative: d[8]})
+     d => node.if.create({condition: d[0], consequent: d[4], alternative: d[8]})
   %}
 | orExpression {% id %}
 
@@ -104,11 +93,11 @@ multiplicativeExpression ->
 | rollExpression {% id %}
 
 rollExpression ->
-  rollExpression _ %diceOperator _ exponentExpression {% d => new RollNode({left: d[0], right: d[4]}) %}
+  rollExpression _ %diceOperator _ exponentExpression {% d => node.roll.create({left: d[0], right: d[4]}) %}
 | singleRollExpression {% id %}
 
 singleRollExpression ->
-  "d" _ singleRollExpression {% d => new RollNode({left: new ConstantNode({value: 1, type: 'number'}), right: d[2]}) %}
+  "d" _ singleRollExpression {% d => node.roll.create({left: node.constant.create({value: 1}), right: d[2]}) %}
 | exponentExpression {% id %}
 
 exponentExpression ->
@@ -116,16 +105,16 @@ exponentExpression ->
 | unaryExpression {% id %}
 
 unaryExpression ->
-  %additiveOperator _ unaryExpression {% d => new UnaryOperatorNode({operator: d[0].value, right: d[2]})%}
+  %additiveOperator _ unaryExpression {% d => node.unaryOperator.create({operator: d[0].value, right: d[2]})%}
 | notExpression {% id %}
 
 notExpression ->
-  %notOperator _ notExpression {% d => new NotOperatorNode({right: d[2]})%}
+  %notOperator _ notExpression {% d => node.notOperator.create({right: d[2]})%}
 | callExpression {% id %}
 
 callExpression ->
   name _ arguments {%
-    d => new CallNode ({functionName: d[0].name, args: d[2]})
+    d => node.call.create({functionName: d[0].name, args: d[2]})
   %}
 | indexExpression {% id %}
 
@@ -135,22 +124,22 @@ arguments ->
   %}
 
 indexExpression ->
-  arrayExpression "[" _ expression _ "]" {% d => new IndexNode ({array: d[0], index: d[3]}) %}
+  arrayExpression "[" _ expression _ "]" {% d => node.index.create({array: d[0], index: d[3]}) %}
 | arrayExpression {% id %}
 
 arrayExpression ->
   "[" _ (expression {% d => d[0] %}):? ( _ %separator _ expression {% d => d[3] %} ):* _ "]" {%
-    d => new ArrayNode({values: d[2] ? [d[2], ...d[3]] : []})
+    d => node.array.create({values: d[2] ? [d[2], ...d[3]] : []})
   %}
 | parenthesizedExpression {% id %}
 
 parenthesizedExpression ->
-  "(" _ expression _ ")" {% d => new ParenthesisNode({content: d[2]}) %}
+  "(" _ expression _ ")" {% d => node.parenthesis.create({content: d[2]}) %}
 | accessorExpression {% id %}
 
 accessorExpression ->
   (%name {% d => d[0].value %}) ( "." %name {% d => d[1].value %} ):+ {%
-    d=> new AccessorNode({name: d[0], path: d[1]})
+    d=> node.accessor.create({name: d[0], path: d[1]})
   %}
 | valueExpression {% id %}
 
@@ -162,17 +151,17 @@ valueExpression ->
 
 # A number or a function of a number
 number ->
-  %number {% d => new ConstantNode({value: +d[0].value, type: 'number'}) %}
+  %number {% d => node.constant.create({value: +d[0].value}) %}
 
 name ->
-  %name {% d => new SymbolNode({name: d[0].value}) %}
+  %name {% d => node.symbol.create({name: d[0].value}) %}
 
 string ->
-  %string {% d => new ConstantNode({value: d[0].value, type: 'string'}) %}
+  %string {% d => node.constant.create({value: d[0].value}) %}
 
 boolean ->
-  "true" {% d => new ConstantNode({value: true, type: 'boolean'}) %}
-| "false" {% d => new ConstantNode({value: false, type: 'boolean'}) %}
+  "true" {% d => node.constant.create({value: true}) %}
+| "false" {% d => node.constant.create({value: false}) %}
 
 _ ->
   null
diff --git a/app/imports/parser/parseTree/IndexNode.js b/app/imports/parser/parseTree/IndexNode.js
deleted file mode 100644
index fdd6c6c6..00000000
--- a/app/imports/parser/parseTree/IndexNode.js
+++ /dev/null
@@ -1,64 +0,0 @@
-import ParseNode from '/imports/parser/parseTree/ParseNode.js';
-import ArrayNode from '/imports/parser/parseTree/ArrayNode.js';
-import ErrorNode from '/imports/parser/parseTree/ErrorNode.js';
-
-export default class IndexNode extends ParseNode {
-  constructor({array, index}) {
-		super(...arguments);
-    this.array = array;
-    this.index = index;
-  }
-  resolve(fn, scope, context){
-    let index = this.index[fn](scope, context);
-    let array = this.array[fn](scope, context);
-
-    if (index.isInteger && array instanceof ArrayNode){
-      if (index.value < 1 || index.value > array.values.length){
-        if (context){
-          context.storeError({
-            type: 'warning',
-            message: `Index of ${index.value} is out of range for an array` +
-              ` of length ${array.values.length}`,
-          });
-        }
-      }
-      let selection = array.values[index.value - 1];
-      if (selection){
-        let result = selection[fn](scope, context);
-        return result;
-      }
-    } else if (fn === 'reduce'){
-      if (!(array instanceof ArrayNode)){
-        return new ErrorNode({
-          node: this,
-          error: 'Can not get the index of a non-array node: ' +
-            this.array.toString() + ' = ' + array.toString(),
-          context,
-        });
-      } else if (!index.isInteger){
-        return new ErrorNode({
-          node: this,
-          error: array.toString() + ' is not an integer index of the array',
-          context,
-        });
-      }
-    }
-    return new IndexNode({
-      index,
-      array,
-      previousNodes: [this],
-    });
-  }
-  toString(){
-    return `${this.array.toString()}[${this.index.toString()}]`;
-  }
-  traverse(fn){
-    fn(this);
-    this.array.traverse(fn);
-    this.index.traverse(fn);
-  }
-  replaceChildren(fn){
-    this.array = this.array.replaceNodes(fn);
-    this.index = this.index.replaceNodes(fn);
-  }
-}
diff --git a/app/imports/parser/parseTree/NotOperatorNode.js b/app/imports/parser/parseTree/NotOperatorNode.js
deleted file mode 100644
index 47aca511..00000000
--- a/app/imports/parser/parseTree/NotOperatorNode.js
+++ /dev/null
@@ -1,34 +0,0 @@
-import ParseNode from '/imports/parser/parseTree/ParseNode.js';
-import ConstantNode from '/imports/parser/parseTree/ConstantNode.js';
-
-export default class NotOperatorNode extends ParseNode {
-  constructor({right}) {
-		super(...arguments);
-    this.right = right;
-  }
-  resolve(fn, scope, context){
-    let rightNode = this.right[fn](scope, context);
-    if (!(rightNode instanceof ConstantNode)){
-      return new NotOperatorNode({
-        right: rightNode,
-      });
-    }
-    let right = rightNode.value;
-    let result = !right;
-    return new ConstantNode({
-      value: result,
-      type: typeof result,
-    });
-  }
-  toString(){
-    let {right} = this;
-    return `!${right.toString()}`;
-  }
-  traverse(fn){
-    fn(this);
-    this.right.traverse(fn);
-  }
-  replaceChildren(fn){
-    this.right = this.right.replaceNodes(fn);
-  }
-}
diff --git a/app/imports/parser/parseTree/OperatorNode.js b/app/imports/parser/parseTree/OperatorNode.js
deleted file mode 100644
index 56633993..00000000
--- a/app/imports/parser/parseTree/OperatorNode.js
+++ /dev/null
@@ -1,71 +0,0 @@
-import ParseNode from '/imports/parser/parseTree/ParseNode.js';
-import ConstantNode from '/imports/parser/parseTree/ConstantNode.js';
-
-export default class OperatorNode extends ParseNode {
-  constructor({left, right, operator, fn}) {
-		super(...arguments);
-    this.left = left;
-    this.right = right;
-    this.fn = fn;
-    this.operator = operator;
-  }
-  resolve(fn, scope, context){
-    let leftNode = this.left[fn](scope, context);
-    let rightNode = this.right[fn](scope, context);
-    let left, right;
-    if (!(leftNode instanceof ConstantNode) || !(rightNode instanceof ConstantNode)){
-      return new OperatorNode({
-        left: leftNode,
-        right: rightNode,
-        operator: this.operator,
-        fn: this.fn,
-      });
-    } else {
-      left = leftNode.value;
-      right = rightNode.value;
-    }
-    let result;
-    switch(this.operator){
-      case '+': result = left + right; break;
-      case '-': result = left - right; break;
-      case '*': result = left * right; break;
-      case '/': result = left / right; break;
-      case '^': result = Math.pow(left, right); break;
-      case '%': result = left % right; break;
-      case '&':
-      case '&&': result = left && right; break;
-      case '|':
-      case '||': result = left || right; break;
-      case '=':
-      case '==':  result = left == right; break;
-      case '===': result = left === right; break;
-      case '!=':  result = left != right; break;
-      case '!==': result = left !== right; break;
-      case '>': result = left > right; break;
-      case '<': result = left < right; break;
-      case '>=': result = left >= right; break;
-      case '<=': result = left <= right; break;
-    }
-    return new ConstantNode({
-      value: result,
-      type: typeof result,
-    });
-  }
-  toString(){
-    let {left, right, operator} = this;
-    // special case of adding a negative number
-    if (operator === '+' && right.isNumber && right.value < 0){
-      return `${left.toString()} - ${-right.value}`
-    }
-    return `${left.toString()} ${operator} ${right.toString()}`;
-  }
-  traverse(fn){
-    fn(this);
-    this.left.traverse(fn);
-    this.right.traverse(fn);
-  }
-  replaceChildren(fn){
-    this.left = this.left.replaceNodes(fn);
-    this.right = this.right.replaceNodes(fn);
-  }
-}
diff --git a/app/imports/parser/parseTree/ParenthesisNode.js b/app/imports/parser/parseTree/ParenthesisNode.js
deleted file mode 100644
index db6b5e14..00000000
--- a/app/imports/parser/parseTree/ParenthesisNode.js
+++ /dev/null
@@ -1,30 +0,0 @@
-import ParseNode from '/imports/parser/parseTree/ParseNode.js';
-
-export default class ParenthesisNode extends ParseNode {
-  constructor({content}) {
-		super(...arguments);
-    this.content = content;
-  }
-  resolve(fn, scope, context){
-    let content = this.content[fn](scope, context);
-    if (
-      fn === 'reduce' ||
-      content.constructor.name === 'ConstantNode' ||
-      content.constructor.name === 'ErrorNode'
-    ){
-      return content;
-    } else {
-      return new ParenthesisNode({content});
-    }
-  }
-  toString(){
-    return `(${this.content.toString()})`;
-  }
-  traverse(fn){
-    fn(this);
-    this.content.traverse(fn);
-  }
-  replaceChildren(fn){
-    this.content = this.content.replaceNodes(fn);
-  }
-}
diff --git a/app/imports/parser/parseTree/ParseNode.js b/app/imports/parser/parseTree/ParseNode.js
deleted file mode 100644
index 740c7b14..00000000
--- a/app/imports/parser/parseTree/ParseNode.js
+++ /dev/null
@@ -1,43 +0,0 @@
-export default class ParseNode {
-  toString(){
-    throw new Meteor.Error('toString not implemented on ' + this.constructor.name);
-  }
-  compile(scope, context){
-    // Returns a ParseNode, a ConstantNode if possible
-    if(this.resolve) {
-      return this.resolve('compile', scope, context);
-    } else {
-      throw new Meteor.Error('Compile not implemented on ' + this.constructor.name);
-    }
-  }
-	// Compile, but turn rolls into arrays
-  roll(scope, context){
-    if (this.resolve){
-      return this.resolve('roll', scope, context);
-    } else {
-      return this.compile(scope, context);
-    }
-  }
-	// Compile, turn rolls into arrays, and reduce those arrays into single values
-	reduce(scope, context){
-    if (this.resolve){
-      return this.resolve('reduce', scope, context);
-    } else {
-      return this.roll(scope, context);
-    }
-	}
-  // If traverse isn't implemented, just apply it to the current node
-  traverse(fn){
-    fn(this);
-  }
-  // replace nodes, only replace nodes if fn returns a value
-  replaceNodes(fn){
-    let newNode = fn(this);
-    if (newNode) {
-      return newNode;
-    } else {
-      if (this.replaceChildren) this.replaceChildren(fn)
-      return this;
-    }
-  }
-}
diff --git a/app/imports/parser/parseTree/RollArrayNode.js b/app/imports/parser/parseTree/RollArrayNode.js
deleted file mode 100644
index 978c20d6..00000000
--- a/app/imports/parser/parseTree/RollArrayNode.js
+++ /dev/null
@@ -1,22 +0,0 @@
-import ParseNode from '/imports/parser/parseTree/ParseNode.js';
-import ConstantNode from '/imports/parser/parseTree/ConstantNode.js';
-
-export default class RollArrayNode extends ParseNode {
-  constructor({values}) {
-		super(...arguments);
-    this.values = values;
-  }
-  compile(){
-    return this;
-  }
-  toString(){
-    return `[${this.values.join(', ')}]`;
-  }
-  reduce(){
-    let total = this.values.reduce((a, b) => a + b);
-    return new ConstantNode({
-      value: total,
-      type: 'number',
-    });
-  }
-}
diff --git a/app/imports/parser/parseTree/RollNode.js b/app/imports/parser/parseTree/RollNode.js
deleted file mode 100644
index 5e1d178f..00000000
--- a/app/imports/parser/parseTree/RollNode.js
+++ /dev/null
@@ -1,70 +0,0 @@
-import ParseNode from '/imports/parser/parseTree/ParseNode.js';
-import RollArrayNode from '/imports/parser/parseTree/RollArrayNode.js';
-import ErrorNode from '/imports/parser/parseTree/ErrorNode.js';
-import roll from '/imports/parser/roll.js';
-import STORAGE_LIMITS from '/imports/constants/STORAGE_LIMITS.js';
-
-export default class RollNode extends ParseNode {
-  constructor({left, right}) {
-		super(...arguments);
-    this.left = left;
-    this.right = right;
-  }
-  compile(scope, context){
-    let left = this.left.compile(scope, context);
-    let right = this.right.compile(scope, context);
-    return new RollNode({left, right, previousNodes: [this]});
-  }
-  toString(){
-    if (
-      this.left.isNumberNode && this.left.value === 1
-    ){
-      return `d${this.right.toString()}`;
-    } else {
-      return `${this.left.toString()}d${this.right.toString()}`;
-    }
-  }
-  roll(scope, context){
-    let left = this.left.reduce(scope, context);
-    let right = this.right.reduce(scope, context);
-    if (!left.isInteger){
-      return new ErrorNode({
-        node: this,
-        error: 'Number of dice is not an integer',
-      });
-    }
-    if (!right.isInteger){
-      return new ErrorNode({
-        node: this,
-        error: 'Dice size is not an integer',
-      });
-    }
-    let number = left.value;
-    if (context.doubleRolls){
-      number *= 2;
-    }
-    if (number > STORAGE_LIMITS.diceRollValuesCount) return new ErrorNode({
-      node: this,
-      error: `Can't roll more than ${STORAGE_LIMITS.diceRollValuesCount} dice at once`,
-      context,
-    });
-    let diceSize = right.value;
-    let values = roll(number, diceSize);
-    if (context){
-      context.storeRoll({number, diceSize, values});
-    }
-    return new RollArrayNode({values});
-  }
-  reduce(scope, context){
-    return this.roll(scope, context).reduce(scope, context);
-  }
-  traverse(fn){
-    fn(this);
-    this.left.traverse(fn);
-    this.right.traverse(fn);
-  }
-  replaceChildren(fn){
-    this.left = this.left.replaceNodes(fn);
-    this.right = this.right.replaceNodes(fn);
-  }
-}
diff --git a/app/imports/parser/parseTree/SymbolNode.js b/app/imports/parser/parseTree/SymbolNode.js
deleted file mode 100644
index 814ea261..00000000
--- a/app/imports/parser/parseTree/SymbolNode.js
+++ /dev/null
@@ -1,53 +0,0 @@
-import ParseNode from '/imports/parser/parseTree/ParseNode.js';
-import ConstantNode from '/imports/parser/parseTree/ConstantNode.js';
-
-export default class SymbolNode extends ParseNode {
-  constructor({name}){
-		super(...arguments);
-    this.name = name;
-  }
-  toString(){
-    return `${this.name}`
-  }
-  compile(scope, context, calledFromReduce = false){
-    let value = scope && scope[this.name];
-    let type = typeof value;
-    // For objects, default to their .value
-    if (type === 'object'){
-      value = value.value;
-      type = typeof value;
-    }
-    // For parse nodes, compile and return
-    if (value instanceof ParseNode){
-      if (calledFromReduce){
-        return value.reduce(scope, context);
-      } else {
-        return value.compile(scope, context);
-      }
-    }
-    if (type === 'string' || type === 'number' || type === 'boolean'){
-      return new ConstantNode({value, type});
-    } else if (type === 'undefined'){
-      return new SymbolNode({
-        name: this.name,
-      });
-    } else {
-      throw new Meteor.Error(`Unexpected case: ${this.name} resolved to ${value}`);
-    }
-  }
-  reduce(scope, context){
-    let result = this.compile(scope, context, true);
-    if (result instanceof SymbolNode){
-      if (context) context.storeError({
-        type: 'info',
-        message: `${result.toString()} not found, set to 0`
-      });
-      return new ConstantNode({
-        type: 'number',
-        value: 0,
-      });
-    } else {
-      return result;
-    }
-  }
-}
diff --git a/app/imports/parser/parseTree/UnaryOperatorNode.js b/app/imports/parser/parseTree/UnaryOperatorNode.js
deleted file mode 100644
index c8109e6a..00000000
--- a/app/imports/parser/parseTree/UnaryOperatorNode.js
+++ /dev/null
@@ -1,40 +0,0 @@
-import ParseNode from '/imports/parser/parseTree/ParseNode.js';
-import ConstantNode from '/imports/parser/parseTree/ConstantNode.js';
-
-export default class UnaryOperatorNode extends ParseNode {
-  constructor({operator, right}) {
-		super(...arguments);
-    this.operator = operator;
-    this.right = right;
-  }
-  resolve(fn, scope, context){
-    let rightNode = this.right[fn](scope, context);
-    if (rightNode.type !== 'number'){
-      return new UnaryOperatorNode({
-        operator: this.operator,
-        right: rightNode,
-      });
-    }
-    let right = rightNode.value;
-    let result;
-    switch(this.operator){
-      case '-': result = -right; break;
-      case '+': result = +right; break;
-    }
-    return new ConstantNode({
-      value: result,
-      type: typeof result,
-    });
-  }
-  toString(){
-    let {right, operator} = this;
-    return `${operator}${right.toString()}`;
-  }
-  traverse(fn){
-    fn(this);
-    this.right.traverse(fn);
-  }
-  replaceChildren(fn){
-    this.right = this.right.replaceNodes(fn);
-  }
-}
diff --git a/app/imports/parser/parseTree/_index.js b/app/imports/parser/parseTree/_index.js
index 571f7e7a..9900c381 100644
--- a/app/imports/parser/parseTree/_index.js
+++ b/app/imports/parser/parseTree/_index.js
@@ -1,5 +1,31 @@
 import accessor from './accessor.js';
+import array from './array.js';
+import call from './call.js';
+import constant from './constant.js';
+import error from './error.js';
+import ifNode from './if.js';
+import index from './index.js';
+import not from './not.js';
+import operator from './operator.js';
+import parenthesis from './parenthesis.js';
+import roll from './roll.js';
+import rollArray from './rollArray.js';
+import symbol from './symbol.js';
+import unaryOperator from './unaryOperator.js';
 
 export default Object.freeze({
   accessor,
+  array,
+  call,
+  constant,
+  error,
+  if: ifNode,
+  index,
+  not,
+  operator,
+  parenthesis,
+  roll,
+  rollArray,
+  symbol,
+  unaryOperator,
 });
diff --git a/app/imports/parser/parseTree/accessor.js b/app/imports/parser/parseTree/accessor.js
index 5ebbf246..8c5b3773 100644
--- a/app/imports/parser/parseTree/accessor.js
+++ b/app/imports/parser/parseTree/accessor.js
@@ -3,7 +3,7 @@ import constant from './constant.js';
 const accessor = {
   create({name, path}) {
     return {
-      type: 'accessor',
+      parseType: 'accessor',
       path,
       name,
     };
@@ -45,12 +45,11 @@ const accessor = {
   },
   reduce(node, scope, context){
     let { result } = accessor.compile(node, scope, context);
-    if (result.type === 'accessor'){
+    if (result.parseType === 'accessor'){
       context.error(`${accessor.toString(result)} not found, set to 0`);
       return {
         result: constant.create({
           value: 0,
-          valueType: 'number',
         }),
         context
       };
diff --git a/app/imports/parser/parseTree/array.js b/app/imports/parser/parseTree/array.js
index 407ab92a..7ee711a6 100644
--- a/app/imports/parser/parseTree/array.js
+++ b/app/imports/parser/parseTree/array.js
@@ -1,10 +1,10 @@
-import constant from './constant.js';
 import resolve, { toString, traverse } from '../resolve.js';
+import constant from './constant.js';
 
 const array = {
   create({values}) {
     return {
-      type: 'array',
+      parseType: 'array',
       values,
     };
   },
@@ -24,7 +24,7 @@ const array = {
     });
     return array.create({values});
   },
-  resolve(fn, node, scope){
+  resolve(fn, node, scope, context){
     let values = node.values.map(node => {
       let { result } = resolve(fn, node, scope, context);
       return result;
diff --git a/app/imports/parser/parseTree/call.js b/app/imports/parser/parseTree/call.js
index 6893dbf4..52b16967 100644
--- a/app/imports/parser/parseTree/call.js
+++ b/app/imports/parser/parseTree/call.js
@@ -1,12 +1,12 @@
 import error from './error.js';
 import constant from './constant.js';
 import functions from '/imports/parser/functions.js';
-import resolve, { toString, traverse, mergeResolvedNodes } from '../resolve.js';
+import resolve, { toString, traverse } from '../resolve.js';
 
 const call = {
   create({functionName, args}) {
     return {
-      type: 'call',
+      parseType: 'call',
       functionName,
       args,
     }
@@ -62,7 +62,7 @@ const call = {
 
     // Map contant nodes to constants before attempting to run the function
     let mappedArgs = resolvedArgs.map(arg => {
-      if (arg.type === 'constant'){
+      if (arg.parseType === 'constant'){
         return arg.value;
       } else {
         return arg;
@@ -125,16 +125,10 @@ const call = {
       } else {
         type = argumentsExpected[index];
       }
-      if (typeof type === 'string'){
-        // Type being a string means a constant node with matching type
-        if (node.valueType !== type) failed = true;
-      } else {
-        // Otherwise check that the node is an instance of the given type
-        if (!(node instanceof type)) failed = true;
-      }
+      if (node.parseType !== type && node.valueType !== type) failed = true;
       if (failed && fn === 'reduce'){
         let typeName = typeof type === 'string' ? type : type.constructor.name;
-        let nodeName = node.type;
+        let nodeName = node.parseType;
         context.error(`Incorrect arguments to ${node.functionName} function` +
           `expected ${typeName} got ${nodeName}`);
       }
diff --git a/app/imports/parser/parseTree/constant.js b/app/imports/parser/parseTree/constant.js
index 4220bc96..e382b897 100644
--- a/app/imports/parser/parseTree/constant.js
+++ b/app/imports/parser/parseTree/constant.js
@@ -1,14 +1,13 @@
 const constant = {
-  create({value, valueType}){
-    if (!valueType) throw `Expected valueType to be set, got ${valueType}`
+  create({value}){
     return {
-      type: 'constant',
-      valueType,
+      parseType: 'constant',
+      valueType: typeof value,
       value,
     }
   },
-  compile(node){
-    return node;
+  compile(node, scope, context){
+    return {result: node, context};
   },
   toString(node){
     return `${node.value}`;
diff --git a/app/imports/parser/parseTree/error.js b/app/imports/parser/parseTree/error.js
index 8533061b..f79ac4af 100644
--- a/app/imports/parser/parseTree/error.js
+++ b/app/imports/parser/parseTree/error.js
@@ -1,13 +1,13 @@
 const error = {
   create({node, error}) {
     return {
-      type: 'error',
+      parseType: 'error',
       node,
       error,
     }
   },
-  compile(node){
-    return node;
+  compile(node, scope, context){
+    return {result: node, context};
   },
   toString(node){
     return node.error.toString();
diff --git a/app/imports/parser/parseTree/if.js b/app/imports/parser/parseTree/if.js
index 369ff924..fc56bf66 100644
--- a/app/imports/parser/parseTree/if.js
+++ b/app/imports/parser/parseTree/if.js
@@ -1,10 +1,9 @@
-import resolve, {traverse, toString, mergeResolvedNodes} from '../resolve';
-import collate from '/imports/api/engine/computation/utility/collate.js';
+import resolve, { traverse, toString } from '../resolve';
 
 const ifNode = {
   create({condition, consequent, alternative}){
     return {
-      type: 'if',
+      parseType: 'if',
       condition,
       consequent,
       alternative,
@@ -14,28 +13,14 @@ const ifNode = {
     let {condition, consequent, alternative} = node;
     return `${toString(condition)} ? ${toString(consequent)} : ${toString(alternative)}`
   },
-  resolve(fn, node, scope){
-    let rest, condition, consequent, alternative;
-    let resolved = {};
+  resolve(fn, node, scope, context){
+    let {result: condition} = resolve(fn, node.condition, scope, context);
 
-    ({result: condition, ...rest} = resolve(fn, node.condition, scope));
-    mergeResolvedNodes(resolved, rest);
-
-    if (condition.type === 'constant'){
+    if (condition.parseType === 'constant'){
       if (condition.value){
-        ({result: consequent, ...rest} = resolve(fn, node.consequent, scope));
-        mergeResolvedNodes(resolved, rest);
-        return {
-          result: consequent,
-          ...resolved
-        };
+        return resolve(fn, node.consequent, scope, context);
       } else {
-        ({result: alternative, ...rest} = resolve(fn, node.alternative, scope));
-        mergeResolvedNodes(resolved, rest);
-        return {
-          result: alternative,
-          ...resolved
-        };
+        return resolve(fn, node.alternative, scope, context);
       }
     } else {
       return {
@@ -44,7 +29,7 @@ const ifNode = {
           consequent: node.consequent,
           alternative: node.alternative,
         }),
-        ...resolved
+        context,
       };
     }
   },
diff --git a/app/imports/parser/parseTree/index.js b/app/imports/parser/parseTree/index.js
index dcb19e2d..17b00a21 100644
--- a/app/imports/parser/parseTree/index.js
+++ b/app/imports/parser/parseTree/index.js
@@ -1,76 +1,73 @@
-import resolve, {traverse, toString, mergeResolvedNodes} from '../resolve';
+import resolve, { traverse, toString } from '../resolve';
+import error from './error';
 
 const index = {
   create({array, index}) {
 		return {
-      type: 'index',
+      parseType: 'index',
       array,
       index,
     }
   },
-  resolve(fn, node, scope){
-    let index, array, rest;
-    let resolved = {};
-    ({result: index, ...rest} = resolve(fn, node.index, scope));
-    mergeResolvedNodes(resolved, rest);
-    ({result: array, ...rest} = resolve(fn, node.array, scope));
-    mergeResolvedNodes(resolved, rest);
+  resolve(fn, node, scope, context){
+    let {result: index} = resolve(fn, node.index, scope, context);
+    let {result: array} = resolve(fn, node.array, scope, context);
 
     if (
       index.valueType === 'number' &&
       Number.isInteger(index.value) &&
-      array.type === 'array'
+      array.parseType === 'array'
     ){
       if (index.value < 1 || index.value > array.values.length){
-        mergeResolvedNodes(resolved, {
-          errors: [{
-            type: 'warning',
-            message: `Index of ${index.value} is out of range for an array` +
-              ` of length ${array.values.length}`,
-          }]
+        context.error({
+          type: 'warning',
+          message: `Index of ${index.value} is out of range for an array` +
+            ` of length ${array.values.length}`,
         });
       }
       let selection = array.values[index.value - 1];
       if (selection){
-        let result;
-        ({result, ...rest} = resolve(fn, selection, scope));
-        mergeResolvedNodes(resolved, rest)
-        return result;
+        return resolve(fn, selection, scope, context);
       }
     } else if (fn === 'reduce'){
-      if (!(array instanceof ArrayNode)){
-        return new ErrorNode({
-          node: node,
-          error: 'Can not get the index of a non-array node: ' +
-            node.array.toString() + ' = ' + array.toString(),
+      if (array.parseType !== 'array'){
+        const message = `Can not get the index of a non-array node: ${node.array.toString()} = ${array.toString()}`
+        context.error(message);
+        return {
+          result: error.create({
+            node,
+            error: message,
+          }),
           context,
-        });
+        };
       } else if (!index.isInteger){
-        return new ErrorNode({
-          node: node,
-          error: array.toString() + ' is not an integer index of the array',
+        const message = `${array.toString()} is not an integer index of the array`
+        context.error(message);
+        return {
+          result: error.create({
+            node,
+            error: message,
+          }),
           context,
-        });
+        };
       }
     }
-    return new IndexNode({
-      index,
-      array,
-      previousNodes: [node],
-    });
+    return {
+      result: index.create({
+        index,
+        array,
+      }),
+      context,
+    };
   },
-  toString(){
-    return `${node.array.toString()}[${node.index.toString()}]`;
+  toString(node){
+    return `${toString(node.array)}[${toString(node.index)}]`;
   },
-  traverse(fn){
+  traverse(node, fn){
     fn(node);
-    node.array.traverse(fn);
-    node.index.traverse(fn);
+    traverse(node.array, fn);
+    traverse(node.index, fn);
   },
-  replaceChildren(fn){
-    node.array = node.array.replaceNodes(fn);
-    node.index = node.index.replaceNodes(fn);
-  }
 }
 
 export default index;
diff --git a/app/imports/parser/parseTree/not.js b/app/imports/parser/parseTree/not.js
new file mode 100644
index 00000000..9488a96c
--- /dev/null
+++ b/app/imports/parser/parseTree/not.js
@@ -0,0 +1,37 @@
+import resolve, { toString, traverse } from '../resolve.js';
+import constant from './constant.js';
+
+const not = {
+  create({right}) {
+    return {
+      parseType: 'not',
+      right,
+    }
+  },
+  resolve(fn, node, scope, context){
+    const {result: right} = resolve(fn, node.right, scope, context);
+    if (right.parseType !== 'constant'){
+      return {
+        result: not.create({
+          right: right,
+        }),
+        context,
+      };
+    }
+    return {
+      result: constant.create({
+        value: !right.value,
+      }),
+      context,
+    };
+  },
+  toString(node){
+    return `!${toString(node.right)}`;
+  },
+  traverse(node, fn){
+    fn(node);
+    traverse(node.right, fn);
+  }
+}
+
+export default not;
diff --git a/app/imports/parser/parseTree/operator.js b/app/imports/parser/parseTree/operator.js
new file mode 100644
index 00000000..7cc4a099
--- /dev/null
+++ b/app/imports/parser/parseTree/operator.js
@@ -0,0 +1,76 @@
+import resolve, { toString, traverse } from '../resolve.js';
+import constant from './constant.js';
+
+const operator = {
+  create({left, right, operator, fn}) {
+    return {
+      parseType: 'operator',
+      left,
+      right,
+      operator,
+      fn
+    };
+  },
+  resolve(fn, node, scope, context){
+    const {result: leftNode} = resolve(fn, node.left, scope, context);
+    const {result: rightNode} = resolve(fn, node.right, scope, context);
+    let left, right;
+    if (leftNode.parseType !== 'constant' || rightNode.parseType !== 'constant'){
+      return {
+        result: operator.create({
+          left: leftNode,
+          right: rightNode,
+          operator: node.operator,
+          fn: node.fn,
+        }),
+        context,
+      };
+    } else {
+      left = leftNode.value;
+      right = rightNode.value;
+    }
+    let result;
+    switch(node.operator){
+      case '+': result = left + right; break;
+      case '-': result = left - right; break;
+      case '*': result = left * right; break;
+      case '/': result = left / right; break;
+      case '^': result = Math.pow(left, right); break;
+      case '%': result = left % right; break;
+      case '&':
+      case '&&': result = left && right; break;
+      case '|':
+      case '||': result = left || right; break;
+      case '=':
+      case '==':  result = left == right; break;
+      case '===': result = left === right; break;
+      case '!=':  result = left != right; break;
+      case '!==': result = left !== right; break;
+      case '>': result = left > right; break;
+      case '<': result = left < right; break;
+      case '>=': result = left >= right; break;
+      case '<=': result = left <= right; break;
+    }
+    return {
+      result: constant.create({
+        value: result,
+      }),
+      context,
+    };
+  },
+  toString(node){
+    let {left, right, operator} = node;
+    // special case of adding a negative number
+    if (operator === '+' && right.valueType === 'number' && right.value < 0){
+      return `${toString(left)} - ${-right.value}`
+    }
+    return `${toString(left)} ${operator} ${toString(right)}`;
+  },
+  traverse(node, fn){
+    fn(node);
+    traverse(node.left, fn);
+    traverse(node.right, fn);
+  },
+}
+
+export default operator;
diff --git a/app/imports/parser/parseTree/parenthesis.js b/app/imports/parser/parseTree/parenthesis.js
new file mode 100644
index 00000000..cd0cfa1a
--- /dev/null
+++ b/app/imports/parser/parseTree/parenthesis.js
@@ -0,0 +1,34 @@
+import resolve, { toString, traverse } from '../resolve.js';
+
+const parenthesis = {
+  create({content}) {
+    return {
+      parseType: 'parenthesis',
+      content,
+    };
+  },
+  resolve(fn, node, scope, context){
+    const {result: content} = resolve(fn, node.content, scope, context);
+    if (
+      fn === 'reduce' ||
+      content.parseType === 'constant' ||
+      content.parseType === 'error'
+    ){
+      return {result: content, context};
+    } else {
+      return {
+        result: parenthesis.create({content}),
+        context
+      };
+    }
+  },
+  toString(node){
+    return `(${toString(node.content)})`;
+  },
+  traverse(node, fn){
+    fn(node);
+    traverse(node.content, fn);
+  }
+}
+
+export default parenthesis;
diff --git a/app/imports/parser/parseTree/roll.js b/app/imports/parser/parseTree/roll.js
new file mode 100644
index 00000000..cc87cbcc
--- /dev/null
+++ b/app/imports/parser/parseTree/roll.js
@@ -0,0 +1,82 @@
+import resolve, { toString, traverse } from '../resolve.js';
+import error from './error.js';
+import rollArray from './rollArray.js';
+import roll from '/imports/parser/roll.js';
+import STORAGE_LIMITS from '/imports/constants/STORAGE_LIMITS.js';
+
+const rollNode = {
+  create({left, right}) {
+    return {
+      parseType: 'roll',
+      left,
+      right,
+    };
+  },
+  compile(node, scope, context){
+    const {result: left} = resolve('compile', node.left, scope, context);
+    const {result: right} = resolve('compile', node.right, scope, context);
+    return {
+      result: rollNode.create({left, right}),
+      context,
+    };
+  },
+  toString(node){
+    if (
+      node.left.parseType === 'number' && node.left.value === 1
+    ){
+      return `d${toString(node.right)}`;
+    } else {
+      return `${toString(node.left)}d${toString(node.right)}`;
+    }
+  },
+  roll(node, scope, context){
+    const {result: left} = resolve('reduce', node.left, scope, context);
+    const {result: right} = resolve('reduce', node.right, scope, context);
+    if (left.parseType !== 'number' && !Number.isInteger(left.value)){
+      return errorResult('Number of dice is not an integer', node, context);
+    }
+    if (!right.isInteger){
+      return errorResult('Dice size is not an integer', node, context);
+    }
+    let number = left.value;
+    if (context.doubleRolls){
+      number *= 2;
+    }
+    if (number > STORAGE_LIMITS.diceRollValuesCount){
+      const message = `Can't roll more than ${STORAGE_LIMITS.diceRollValuesCount} dice at once`;
+      return errorResult(message, node, context);
+    }
+    let diceSize = right.value;
+    let values = roll(number, diceSize);
+    if (context){
+      context.storeRoll({number, diceSize, values});
+    }
+    return {
+      result: rollArray.create({
+        values,
+        diceSize,
+        diceNum: left.value,
+      }),
+      context
+    };
+  },
+  reduce(node, scope, context){
+    const {result} = rollNode.roll(node, scope, context);
+    return resolve('reduce', result, scope, context);
+  },
+  traverse(node, fn){
+    fn(node);
+    traverse(node.left, fn);
+    traverse(node.right, fn);
+  },
+}
+
+function errorResult(message, node, context){
+  context.error(message);
+  return {
+    result: error.create({ node, error: message }),
+    context,
+  };
+}
+
+export default rollNode;
diff --git a/app/imports/parser/parseTree/rollArray.js b/app/imports/parser/parseTree/rollArray.js
new file mode 100644
index 00000000..bb778947
--- /dev/null
+++ b/app/imports/parser/parseTree/rollArray.js
@@ -0,0 +1,35 @@
+import constant from './constant.js';
+
+const rollArray = {
+  constructor({values, diceSize, diceNum}) {
+		return {
+      parseType: 'rollArray',
+      values,
+      diceSize,
+      diceNum,
+    };
+  },
+  compile(node, scope, context){
+    return {
+      result: node,
+      context
+    };
+  },
+  toString(node){
+    return `[${node.values.join(', ')}]`;
+  },
+  reduce(node, scope, context){
+    const total = node.values.reduce((a, b) => a + b, 0);
+    return {
+      result: constant.create({
+        value: total,
+      }),
+      context,
+    };
+  },
+  traverse(node, fn){
+    return fn(node);
+  }
+}
+
+export default rollArray;
diff --git a/app/imports/parser/parseTree/symbol.js b/app/imports/parser/parseTree/symbol.js
new file mode 100644
index 00000000..208baa66
--- /dev/null
+++ b/app/imports/parser/parseTree/symbol.js
@@ -0,0 +1,61 @@
+import resolve from '../resolve.js';
+import constant from './constant.js';
+
+const symbol = {
+  create({name}){
+    return {
+      parseType: 'symbol',
+      name,
+    };
+  },
+  toString(node){
+    return `${node.name}`
+  },
+  compile(node, scope, context, calledFromReduce = false){
+    let value = scope && scope[node.name];
+    let type = typeof value;
+    // For objects, default to their .value
+    if (type === 'object'){
+      value = value.value;
+      type = typeof value;
+    }
+    // For parse nodes, compile and return
+    if (value?.parseType){
+      if (calledFromReduce){
+        return resolve('reduce', value, scope, context);
+      } else {
+        return resolve('compile', value, scope, context);
+      }
+    }
+    if (type === 'string' || type === 'number' || type === 'boolean'){
+      return {
+        result: constant.create({value}),
+        context,
+      };
+    } else if (type === 'undefined'){
+      return {
+        result: symbol.create({name: node.name}),
+        context,
+      };
+    } else {
+      throw new Meteor.Error(`Unexpected case: ${node.name} resolved to ${value}`);
+    }
+  },
+  reduce(node, scope, context){
+    let {result} = symbol.compile(node, scope, context, true);
+    if (result.parseType === 'symbol'){
+      context.error({
+        type: 'info',
+        message: `${result.toString()} not found, set to 0`
+      });
+      return {
+        result: constant.create({value: 0}),
+        context,
+      };
+    } else {
+      return {result, context};
+    }
+  }
+}
+
+export default symbol;
diff --git a/app/imports/parser/parseTree/unaryOperator.js b/app/imports/parser/parseTree/unaryOperator.js
new file mode 100644
index 00000000..1b348f90
--- /dev/null
+++ b/app/imports/parser/parseTree/unaryOperator.js
@@ -0,0 +1,46 @@
+import resolve, { toString, traverse } from '../resolve.js';
+import constant from './constant.js';
+
+const unaryOperator = {
+  create({operator, right}) {
+    return {
+      parseType: 'unaryOperator',
+      operator,
+      right,
+    };
+  },
+  resolve(fn, node, scope, context){
+    const {result: rightNode} = resolve(fn, node.right, scope, context);
+    if (rightNode.parseType !== 'number'){
+      return {
+        result: unaryOperator.create({
+          operator: node.operator,
+          right: rightNode,
+        }),
+        context,
+      };
+    }
+    let right = rightNode.value;
+    let result;
+    switch(node.operator){
+      case '-': result = -right; break;
+      case '+': result = +right; break;
+    }
+    return {
+      result: constant.create({
+        value: result,
+        parseType: typeof result,
+      }),
+      context,
+    };
+  },
+  toString(node){
+    return `${node.operator}${toString(node.right)}`;
+  },
+  traverse(node, fn){
+    fn(node);
+    traverse(node.right, fn);
+  },
+};
+
+export default unaryOperator;
diff --git a/app/imports/parser/parser.js b/app/imports/parser/parser.js
index 13f24579..8532055b 100644
--- a/app/imports/parser/parser.js
+++ b/app/imports/parser/parser.js
@@ -7,20 +7,6 @@ export default function parser(){
   return new nearley.Parser(nearleyGrammar);
 }
 
-export class CompilationContext {
-  constructor({doubleRolls} = {}){
-    this.errors = [];
-    this.rolls = [];
-    this.doubleRolls = doubleRolls;
-  }
-  storeError(e){
-    this.errors.push(e);
-  }
-  storeRoll(r){
-    this.rolls.push(r);
-  }
-}
-
 export function parse(string){
   let parser = new nearley.Parser(nearleyGrammar);
   parser.feed(string);
diff --git a/app/imports/parser/resolve.js b/app/imports/parser/resolve.js
index 86d2fad6..add29f25 100644
--- a/app/imports/parser/resolve.js
+++ b/app/imports/parser/resolve.js
@@ -1,13 +1,11 @@
-import nodeTypeIndex from './parseTree/index.js';
-import collate from '/imports/api/engine/computation/utility/collate.js';
-import Context from './ResolveContext.js';
+import nodeTypeIndex from './parseTree/_index.js';
 
 // Takes a parse ndoe and computes it to a set detail level
 // returns {result, context}
 export default function resolve(fn, node, scope, context = new Context()){
-  let type = nodeTypeIndex[node.type];
+  let type = nodeTypeIndex[node.parseType];
   if (!type){
-    throw new Meteor.Error(`Parse node type: ${node.type} not implemented`);
+    throw new Meteor.Error(`Parse node type: ${node.parseType} not implemented`);
   }
   if (type.resolve){
     return type.resolve(fn, node, scope, context);
@@ -18,28 +16,49 @@ export default function resolve(fn, node, scope, context = new Context()){
   } else if (type.compile){
     return type.compile(node, scope, context)
   } else {
-    throw new Meteor.Error('Compile not implemented on ' + node.type);
+    throw new Meteor.Error('Compile not implemented on ' + node.parseType);
   }
 }
 
 export function toString(node){
-  let type = nodeTypeIndex[node.type];
+  let type = nodeTypeIndex[node.parseType];
   if (!type.toString){
-    throw new Meteor.Error('toString not implemented on ' + node.type);
+    throw new Meteor.Error('toString not implemented on ' + node.parseType);
   }
   return type.toString(node);
 }
 
 export function traverse(node, fn){
-  let type = nodeTypeIndex[node.type];
+  if (!node) return;
+  let type = nodeTypeIndex[node.parseType];
+  if (!type){
+    console.error(node);
+    throw new Meteor.Error('Not valid parse node');
+  }
   if (type.traverse){
     return type.traverse(node, fn);
   }
   return fn(node);
 }
 
-export function mergeResolvedNodes(main, other){
-  main.errors = collate(main.errors, other.errors);
-  main.rolls = collate(main.rolls, other.rolls);
-  return main;
+export class Context {
+  constructor({errors = [], rolls = [], doubleRolls} = {}){
+    this.errors = errors;
+    this.rolls = rolls;
+    this.doubleRolls = doubleRolls;
+  }
+  error(e){
+    if (!e) return;
+    if (typeof e === 'string'){
+      this.errors.push({
+        type: 'error',
+        message: e,
+      });
+    } else {
+      this.errors.push(e);
+    }
+  }
+  roll(r){
+    this.rolls.push(r);
+  }
 }