diff --git a/dist/lindenmayer.browser.js b/dist/lindenmayer.browser.js
index 8b2e177..c2fca90 100644
--- a/dist/lindenmayer.browser.js
+++ b/dist/lindenmayer.browser.js
@@ -127,7 +127,7 @@ function normalizeProduction(p, forceObjects) {
   return p;
 }
 
-function LSystem({ axiom = '', productions, finals, branchSymbols = '', ignoredSymbols = '', allowClassicSyntax = true, classicParametricSyntax = false, forceObjects = false, debug = false }) {
+function LSystem({ axiom = '', productions, finals, branchSymbols = '[]', ignoredSymbols = '+-&^/|\\', allowClassicSyntax = true, classicParametricSyntax = false, forceObjects = false, debug = false }) {
 
 	// TODO: forceObject to be more intelligent based on other productions??
 
@@ -167,7 +167,7 @@ function LSystem({ axiom = '', productions, finals, branchSymbols = '', ignoredS
 
 		// Apply production transformers and normalizations
 		if (this.allowClassicSyntax === true) {
-			newProduction = transformClassicCSProduction(newProduction, this.ignoredSymbols);
+			newProduction = transformClassicCSProduction(newProduction);
 		}
 
 		newProduction = normalizeProduction(newProduction, this.forceObjects);
@@ -253,11 +253,11 @@ function LSystem({ axiom = '', productions, finals, branchSymbols = '', ignoredS
 			precheck = false;
 		} else if (contextSensitive) {
 			if (p.leftCtx !== undefined && p.rightCtx !== undefined) {
-				precheck = this.match({ direction: 'left', match: p.leftCtx, index: index, branchSymbols: '[]' }).result && this.match({ direction: 'right', match: p.rightCtx, index: index, branchSymbols: '[]', ignoredSymbols: ignoredSymbols }).result;
+				precheck = this.match({ direction: 'left', match: p.leftCtx, index: index, branchSymbols, ignoredSymbols }).result;
 			} else if (p.leftCtx !== undefined) {
-				precheck = this.match({ direction: 'left', match: p.leftCtx, index: index, branchSymbols: '[]' }).result;
+				precheck = this.match({ direction: 'left', match: p.leftCtx, index: index, branchSymbols, ignoredSymbols }).result;
 			} else if (p.rightCtx !== undefined) {
-				precheck = this.match({ direction: 'right', match: p.rightCtx, index: index, branchSymbols: '[]' }).result;
+				precheck = this.match({ direction: 'right', match: p.rightCtx, index: index, branchSymbols, ignoredSymbols }).result;
 			}
 		}
 
diff --git a/dist/lindenmayer.browser.min.js b/dist/lindenmayer.browser.min.js
index c52e5ab..07e712c 100644
--- a/dist/lindenmayer.browser.min.js
+++ b/dist/lindenmayer.browser.min.js
@@ -1 +1 @@
-var LSystem=function(){"use strict";function t(t){let s,i=t[0].match(/(.+)<(.)/),o=t[0].match(/(.)>(.+)/);if(null===i&&null===o)return t;let e=t[1].successor||t[1].successors?t[1]:{successor:t[1]};return null!==i&&(s=i[2],e.leftCtx=i[1]),null!==o&&(s=o[1],e.rightCtx=o[2]),[s,e]}function s(t){if("string"!=typeof t&&t instanceof String==!1)return t;let s=[];for(let i of t)s.push({symbol:i});return s}function i(t,i){return t[1]=function t(i,o){if(i.hasOwnProperty("successors"))for(var e=0;e<i.successors.length;e++)i.successors[e]=t(i.successors[e],o);else!1===i.hasOwnProperty("successor")&&(i={successor:i});return o&&i.hasOwnProperty("successor")&&(i.successor=s(i.successor)),i}(t[1],i),t}function LSystem({axiom:o="",productions:e,finals:r,branchSymbols:n="",ignoredSymbols:c="",allowClassicSyntax:a=!0,classicParametricSyntax:h=!1,forceObjects:l=!1,debug:u=!1}){return this.setAxiom=function(t){this.axiom=this.forceObjects?s(t):t},this.getRaw=function(){return this.axiom},this.getString=function(t=!0){return"string"==typeof this.axiom?this.axiom:!0===t?this.axiom.reduce((t,s)=>{if(void 0===s.symbol)throw console.log("found:",s),new Error("L-Systems that use only objects as symbols (eg: {symbol: 'F', params: []}), cant use string symbols (eg. 'F')! Check if you always return objects in your productions and no strings.");return t+s.symbol},""):JSON.stringify(this.axiom)},this.getStringResult=this.getString,this.setProduction=function(s,o,e=!1){let r=[s,o];if(void 0===r)throw new Error("no production specified.");if(o.successor&&o.successors)throw new Error('You can not have both a "successor" and a "successors" field in your production!');if(!0===this.allowClassicSyntax&&(r=t(r,this.ignoredSymbols)),(r=i(r,this.forceObjects))[1].isStochastic=void 0!==r[1].successors&&r[1].successors.every(t=>void 0!==t.weight),r[1].isStochastic){r[1].weightSum=0;for(let t of r[1].successors)r[1].weightSum+=t.weight}let n=r[0];if(!0===e&&this.productions.has(n)){let t=this.productions.get(n),s=t.successor,i=t.successors;s&&!i&&(t={successors:[t]}),t.successors.push(r[1]),this.productions.set(n,t)}else this.productions.set(n,r[1])},this.setProductions=function(t){if(void 0===t)throw new Error("no production specified.");this.clearProductions();for(let s of Object.entries(t)){let t=s[0],i=s[1];this.setProduction(t,i,!0)}},this.clearProductions=function(){this.productions=new Map},this.setFinal=function(t,s){let i=[t,s];if(void 0===i)throw new Error("no final specified.");this.finals.set(i[0],i[1])},this.setFinals=function(t){if(void 0===t)throw new Error("no finals specified.");this.finals=new Map;for(let s in t)t.hasOwnProperty(s)&&this.setFinal(s,t[s])},this.getProductionResult=function(t,s,i,o,e=!1){let r=void 0!==t.leftCtx||void 0!==t.rightCtx,n=!1,a=!0;if(void 0!==t.condition&&!1===t.condition({index:s,currentAxiom:this.axiom,part:i,params:o})?a=!1:r&&(void 0!==t.leftCtx&&void 0!==t.rightCtx?a=this.match({direction:"left",match:t.leftCtx,index:s,branchSymbols:"[]"}).result&&this.match({direction:"right",match:t.rightCtx,index:s,branchSymbols:"[]",ignoredSymbols:c}).result:void 0!==t.leftCtx?a=this.match({direction:"left",match:t.leftCtx,index:s,branchSymbols:"[]"}).result:void 0!==t.rightCtx&&(a=this.match({direction:"right",match:t.rightCtx,index:s,branchSymbols:"[]"}).result)),!1===a)n=!1;else if(t.successors){var h,l;t.isStochastic&&(l=Math.random()*t.weightSum,h=0);for(let e of t.successors){if(t.isStochastic&&(h+=e.weight)<l)continue;let r=this.getProductionResult(e,s,i,o,!0);if(void 0!==r&&!1!==r){n=r;break}}}else n="function"==typeof t.successor?t.successor({index:s,currentAxiom:this.axiom,part:i,params:o}):t.successor;return n||(e?n:i)},this.applyProductions=function(){let t="string"==typeof this.axiom?"":[],s=0;for(let i of this.axiom){let o=i.symbol||i,e=i.params||[],r=i;if(this.productions.has(o)){let t=this.productions.get(o);r=this.getProductionResult(t,s,i,e)}"string"==typeof t?t+=r:r instanceof Array?Array.prototype.push.apply(t,r):t.push(r),s++}return this.axiom=t,t},this.iterate=function(t=1){let s;this.iterations=t;for(let i=0;i<t;i++)s=this.applyProductions();return s},this.final=function(t){let s=0;for(let i of this.axiom){let o=i;if("object"==typeof i&&i.symbol&&(o=i.symbol),this.finals.has(o)){let e=this.finals.get(o),r=typeof e;if("function"!==r)throw Error("'"+o+"' has an object for a final function. But it is __not a function__ but a "+r+"!");e({index:s,part:i},t)}s++}},this.match=function({axiom_:t,match:s,ignoredSymbols:i,branchSymbols:o,index:e,direction:r}){let n=0,c=0;t=t||this.axiom,void 0===o&&(o=void 0!==this.branchSymbols?this.branchSymbols:[]),void 0===i&&(i=void 0!==this.ignoredSymbols?this.ignoredSymbols:[]);let a,h,l,u,f,m,d,g=[];if("right"===r){if(u=m=1,l=e+1,f=0,d=s.length,o.length>0){var y=o;a=y[0],h=y[1]}}else{if("left"!==r)throw Error(r,"is not a valid direction for matching.");if(u=m=-1,l=e-1,f=s.length-1,d=-1,o.length>0){var p=o;h=p[0],a=p[1]}}for(;l<t.length&&l>=0;l+=u){let o=t[l].symbol||t[l],e=s[f];if(o===e){if((0===n||c>0)&&(o===a?(c++,n++,f+=m):o===h?(c=Math.max(0,c-1),n=Math.max(0,n-1),0===c&&(f+=m)):(g.push(l),f+=m)),f===d)return{result:!0,matchIndices:g}}else if(o===a)n++,c>0&&c++;else if(o===h)n=Math.max(0,n-1),c>0&&(c=Math.max(0,c-1));else if((0===n||c>0&&e!==h)&&!1===i.includes(o))return{result:!1,matchIndices:g}}return{result:!1,matchIndices:g}},this.ignoredSymbols=c,this.debug=u,this.branchSymbols=n,this.allowClassicSyntax=a,this.classicParametricSyntax=h,this.forceObjects=l,this.setAxiom(o),this.clearProductions(),e&&this.setProductions(e),r&&this.setFinals(r),this}return LSystem.transformClassicStochasticProductions=function(t){return function(){let s=t,i=s.length,o=Math.random();for(let t=0;t<i;t++)if(o<=(t+1)/i)return s[t];console.error("Should have returned a result of the list, something is wrong here with the random numbers?.")}},LSystem.transformClassicCSProduction=t,LSystem.transformClassicParametricAxiom=function(t){let s=t.replace(/\s+/g,"").split(/[\(\)]/),i=[];for(let t=0;t<s.length-1;t+=2){let o=s[t+1].split(",").map(Number);i.push({symbol:s[t],params:o})}},LSystem.testClassicParametricSyntax=function(t){return/\(.+\)/.test(t)},LSystem}();
+var LSystem=function(){"use strict";function t(t){let s,i=t[0].match(/(.+)<(.)/),o=t[0].match(/(.)>(.+)/);if(null===i&&null===o)return t;let e=t[1].successor||t[1].successors?t[1]:{successor:t[1]};return null!==i&&(s=i[2],e.leftCtx=i[1]),null!==o&&(s=o[1],e.rightCtx=o[2]),[s,e]}function s(t){if("string"!=typeof t&&t instanceof String==!1)return t;let s=[];for(let i of t)s.push({symbol:i});return s}function i(t,i){return t[1]=function t(i,o){if(i.hasOwnProperty("successors"))for(var e=0;e<i.successors.length;e++)i.successors[e]=t(i.successors[e],o);else!1===i.hasOwnProperty("successor")&&(i={successor:i});return o&&i.hasOwnProperty("successor")&&(i.successor=s(i.successor)),i}(t[1],i),t}function LSystem({axiom:o="",productions:e,finals:r,branchSymbols:n="[]",ignoredSymbols:c="+-&^/|\\",allowClassicSyntax:a=!0,classicParametricSyntax:h=!1,forceObjects:l=!1,debug:u=!1}){return this.setAxiom=function(t){this.axiom=this.forceObjects?s(t):t},this.getRaw=function(){return this.axiom},this.getString=function(t=!0){return"string"==typeof this.axiom?this.axiom:!0===t?this.axiom.reduce((t,s)=>{if(void 0===s.symbol)throw console.log("found:",s),new Error("L-Systems that use only objects as symbols (eg: {symbol: 'F', params: []}), cant use string symbols (eg. 'F')! Check if you always return objects in your productions and no strings.");return t+s.symbol},""):JSON.stringify(this.axiom)},this.getStringResult=this.getString,this.setProduction=function(s,o,e=!1){let r=[s,o];if(void 0===r)throw new Error("no production specified.");if(o.successor&&o.successors)throw new Error('You can not have both a "successor" and a "successors" field in your production!');if(!0===this.allowClassicSyntax&&(r=t(r)),(r=i(r,this.forceObjects))[1].isStochastic=void 0!==r[1].successors&&r[1].successors.every(t=>void 0!==t.weight),r[1].isStochastic){r[1].weightSum=0;for(let t of r[1].successors)r[1].weightSum+=t.weight}let n=r[0];if(!0===e&&this.productions.has(n)){let t=this.productions.get(n),s=t.successor,i=t.successors;s&&!i&&(t={successors:[t]}),t.successors.push(r[1]),this.productions.set(n,t)}else this.productions.set(n,r[1])},this.setProductions=function(t){if(void 0===t)throw new Error("no production specified.");this.clearProductions();for(let s of Object.entries(t)){let t=s[0],i=s[1];this.setProduction(t,i,!0)}},this.clearProductions=function(){this.productions=new Map},this.setFinal=function(t,s){let i=[t,s];if(void 0===i)throw new Error("no final specified.");this.finals.set(i[0],i[1])},this.setFinals=function(t){if(void 0===t)throw new Error("no finals specified.");this.finals=new Map;for(let s in t)t.hasOwnProperty(s)&&this.setFinal(s,t[s])},this.getProductionResult=function(t,s,i,o,e=!1){let r=void 0!==t.leftCtx||void 0!==t.rightCtx,a=!1,h=!0;if(void 0!==t.condition&&!1===t.condition({index:s,currentAxiom:this.axiom,part:i,params:o})?h=!1:r&&(void 0!==t.leftCtx&&void 0!==t.rightCtx?h=this.match({direction:"left",match:t.leftCtx,index:s,branchSymbols:n,ignoredSymbols:c}).result:void 0!==t.leftCtx?h=this.match({direction:"left",match:t.leftCtx,index:s,branchSymbols:n,ignoredSymbols:c}).result:void 0!==t.rightCtx&&(h=this.match({direction:"right",match:t.rightCtx,index:s,branchSymbols:n,ignoredSymbols:c}).result)),!1===h)a=!1;else if(t.successors){var l,u;t.isStochastic&&(u=Math.random()*t.weightSum,l=0);for(let e of t.successors){if(t.isStochastic&&(l+=e.weight)<u)continue;let r=this.getProductionResult(e,s,i,o,!0);if(void 0!==r&&!1!==r){a=r;break}}}else a="function"==typeof t.successor?t.successor({index:s,currentAxiom:this.axiom,part:i,params:o}):t.successor;return a||(e?a:i)},this.applyProductions=function(){let t="string"==typeof this.axiom?"":[],s=0;for(let i of this.axiom){let o=i.symbol||i,e=i.params||[],r=i;if(this.productions.has(o)){let t=this.productions.get(o);r=this.getProductionResult(t,s,i,e)}"string"==typeof t?t+=r:r instanceof Array?Array.prototype.push.apply(t,r):t.push(r),s++}return this.axiom=t,t},this.iterate=function(t=1){let s;this.iterations=t;for(let i=0;i<t;i++)s=this.applyProductions();return s},this.final=function(t){let s=0;for(let i of this.axiom){let o=i;if("object"==typeof i&&i.symbol&&(o=i.symbol),this.finals.has(o)){let e=this.finals.get(o),r=typeof e;if("function"!==r)throw Error("'"+o+"' has an object for a final function. But it is __not a function__ but a "+r+"!");e({index:s,part:i},t)}s++}},this.match=function({axiom_:t,match:s,ignoredSymbols:i,branchSymbols:o,index:e,direction:r}){let n=0,c=0;t=t||this.axiom,void 0===o&&(o=void 0!==this.branchSymbols?this.branchSymbols:[]),void 0===i&&(i=void 0!==this.ignoredSymbols?this.ignoredSymbols:[]);let a,h,l,u,f,d,m,g=[];if("right"===r){if(u=d=1,l=e+1,f=0,m=s.length,o.length>0){var y=o;a=y[0],h=y[1]}}else{if("left"!==r)throw Error(r,"is not a valid direction for matching.");if(u=d=-1,l=e-1,f=s.length-1,m=-1,o.length>0){var p=o;h=p[0],a=p[1]}}for(;l<t.length&&l>=0;l+=u){let o=t[l].symbol||t[l],e=s[f];if(o===e){if((0===n||c>0)&&(o===a?(c++,n++,f+=d):o===h?(c=Math.max(0,c-1),n=Math.max(0,n-1),0===c&&(f+=d)):(g.push(l),f+=d)),f===m)return{result:!0,matchIndices:g}}else if(o===a)n++,c>0&&c++;else if(o===h)n=Math.max(0,n-1),c>0&&(c=Math.max(0,c-1));else if((0===n||c>0&&e!==h)&&!1===i.includes(o))return{result:!1,matchIndices:g}}return{result:!1,matchIndices:g}},this.ignoredSymbols=c,this.debug=u,this.branchSymbols=n,this.allowClassicSyntax=a,this.classicParametricSyntax=h,this.forceObjects=l,this.setAxiom(o),this.clearProductions(),e&&this.setProductions(e),r&&this.setFinals(r),this}return LSystem.transformClassicStochasticProductions=function(t){return function(){let s=t,i=s.length,o=Math.random();for(let t=0;t<i;t++)if(o<=(t+1)/i)return s[t];console.error("Should have returned a result of the list, something is wrong here with the random numbers?.")}},LSystem.transformClassicCSProduction=t,LSystem.transformClassicParametricAxiom=function(t){let s=t.replace(/\s+/g,"").split(/[\(\)]/),i=[];for(let t=0;t<s.length-1;t+=2){let o=s[t+1].split(",").map(Number);i.push({symbol:s[t],params:o})}},LSystem.testClassicParametricSyntax=function(t){return/\(.+\)/.test(t)},LSystem}();
diff --git a/dist/lindenmayer.es.js b/dist/lindenmayer.es.js
index db35ff6..3dcf0b2 100644
--- a/dist/lindenmayer.es.js
+++ b/dist/lindenmayer.es.js
@@ -124,7 +124,7 @@ function normalizeProduction(p, forceObjects) {
   return p;
 }
 
-function LSystem({ axiom = '', productions, finals, branchSymbols = '', ignoredSymbols = '', allowClassicSyntax = true, classicParametricSyntax = false, forceObjects = false, debug = false }) {
+function LSystem({ axiom = '', productions, finals, branchSymbols = '[]', ignoredSymbols = '+-&^/|\\', allowClassicSyntax = true, classicParametricSyntax = false, forceObjects = false, debug = false }) {
 
 	// TODO: forceObject to be more intelligent based on other productions??
 
@@ -164,7 +164,7 @@ function LSystem({ axiom = '', productions, finals, branchSymbols = '', ignoredS
 
 		// Apply production transformers and normalizations
 		if (this.allowClassicSyntax === true) {
-			newProduction = transformClassicCSProduction(newProduction, this.ignoredSymbols);
+			newProduction = transformClassicCSProduction(newProduction);
 		}
 
 		newProduction = normalizeProduction(newProduction, this.forceObjects);
@@ -250,11 +250,11 @@ function LSystem({ axiom = '', productions, finals, branchSymbols = '', ignoredS
 			precheck = false;
 		} else if (contextSensitive) {
 			if (p.leftCtx !== undefined && p.rightCtx !== undefined) {
-				precheck = this.match({ direction: 'left', match: p.leftCtx, index: index, branchSymbols: '[]' }).result && this.match({ direction: 'right', match: p.rightCtx, index: index, branchSymbols: '[]', ignoredSymbols: ignoredSymbols }).result;
+				precheck = this.match({ direction: 'left', match: p.leftCtx, index: index, branchSymbols, ignoredSymbols }).result;
 			} else if (p.leftCtx !== undefined) {
-				precheck = this.match({ direction: 'left', match: p.leftCtx, index: index, branchSymbols: '[]' }).result;
+				precheck = this.match({ direction: 'left', match: p.leftCtx, index: index, branchSymbols, ignoredSymbols }).result;
 			} else if (p.rightCtx !== undefined) {
-				precheck = this.match({ direction: 'right', match: p.rightCtx, index: index, branchSymbols: '[]' }).result;
+				precheck = this.match({ direction: 'right', match: p.rightCtx, index: index, branchSymbols, ignoredSymbols }).result;
 			}
 		}
 
diff --git a/dist/lindenmayer.es.min.js b/dist/lindenmayer.es.min.js
index dacdd44..6e8a7f4 100644
--- a/dist/lindenmayer.es.min.js
+++ b/dist/lindenmayer.es.min.js
@@ -1 +1 @@
-function t(t){return function(){let s=t,i=s.length,o=Math.random();for(let t=0;t<i;t++){if(o<=(t+1)/i)return s[t]}console.error("Should have returned a result of the list, something is wrong here with the random numbers?.")}}function s(t){return/\(.+\)/.test(t)}function i(t){let s=t.replace(/\s+/g,"").split(/[\(\)]/),i=[];for(let t=0;t<s.length-1;t+=2){let o=s[t+1].split(",").map(Number);i.push({symbol:s[t],params:o})}}function o(t){let s,i=t[0].match(/(.+)<(.)/),o=t[0].match(/(.)>(.+)/);if(null===i&&null===o)return t;let e=t[1].successor||t[1].successors?t[1]:{successor:t[1]};return null!==i&&(s=i[2],e.leftCtx=i[1]),null!==o&&(s=o[1],e.rightCtx=o[2]),[s,e]}function e(t){if("string"!=typeof t&&t instanceof String==!1)return t;let s=[];for(let i of t)s.push({symbol:i});return s}function r(t,s){if(t.hasOwnProperty("successors"))for(var i=0;i<t.successors.length;i++)t.successors[i]=r(t.successors[i],s);else!1===t.hasOwnProperty("successor")&&(t={successor:t});return s&&t.hasOwnProperty("successor")&&(t.successor=e(t.successor)),t}function n(t,s){return t[1]=r(t[1],s),t}function LSystem({axiom:t="",productions:s,finals:i,branchSymbols:r="",ignoredSymbols:c="",allowClassicSyntax:a=!0,classicParametricSyntax:h=!1,forceObjects:l=!1,debug:u=!1}){return this.setAxiom=function(t){this.axiom=this.forceObjects?e(t):t},this.getRaw=function(){return this.axiom},this.getString=function(t=!0){return"string"==typeof this.axiom?this.axiom:!0===t?this.axiom.reduce((t,s)=>{if(void 0===s.symbol)throw console.log("found:",s),new Error("L-Systems that use only objects as symbols (eg: {symbol: 'F', params: []}), cant use string symbols (eg. 'F')! Check if you always return objects in your productions and no strings.");return t+s.symbol},""):JSON.stringify(this.axiom)},this.getStringResult=this.getString,this.setProduction=function(t,s,i=!1){let e=[t,s];if(void 0===e)throw new Error("no production specified.");if(s.successor&&s.successors)throw new Error('You can not have both a "successor" and a "successors" field in your production!');if(!0===this.allowClassicSyntax&&(e=o(e,this.ignoredSymbols)),(e=n(e,this.forceObjects))[1].isStochastic=void 0!==e[1].successors&&e[1].successors.every(t=>void 0!==t.weight),e[1].isStochastic){e[1].weightSum=0;for(let t of e[1].successors)e[1].weightSum+=t.weight}let r=e[0];if(!0===i&&this.productions.has(r)){let t=this.productions.get(r),s=t.successor,i=t.successors;s&&!i&&(t={successors:[t]}),t.successors.push(e[1]),this.productions.set(r,t)}else this.productions.set(r,e[1])},this.setProductions=function(t){if(void 0===t)throw new Error("no production specified.");this.clearProductions();for(let s of Object.entries(t)){let t=s[0],i=s[1];this.setProduction(t,i,!0)}},this.clearProductions=function(){this.productions=new Map},this.setFinal=function(t,s){let i=[t,s];if(void 0===i)throw new Error("no final specified.");this.finals.set(i[0],i[1])},this.setFinals=function(t){if(void 0===t)throw new Error("no finals specified.");this.finals=new Map;for(let s in t)t.hasOwnProperty(s)&&this.setFinal(s,t[s])},this.getProductionResult=function(t,s,i,o,e=!1){let r=void 0!==t.leftCtx||void 0!==t.rightCtx,n=!1,a=!0;if(void 0!==t.condition&&!1===t.condition({index:s,currentAxiom:this.axiom,part:i,params:o})?a=!1:r&&(void 0!==t.leftCtx&&void 0!==t.rightCtx?a=this.match({direction:"left",match:t.leftCtx,index:s,branchSymbols:"[]"}).result&&this.match({direction:"right",match:t.rightCtx,index:s,branchSymbols:"[]",ignoredSymbols:c}).result:void 0!==t.leftCtx?a=this.match({direction:"left",match:t.leftCtx,index:s,branchSymbols:"[]"}).result:void 0!==t.rightCtx&&(a=this.match({direction:"right",match:t.rightCtx,index:s,branchSymbols:"[]"}).result)),!1===a)n=!1;else if(t.successors){var h,l;t.isStochastic&&(l=Math.random()*t.weightSum,h=0);for(let e of t.successors){if(t.isStochastic&&(h+=e.weight)<l)continue;let r=this.getProductionResult(e,s,i,o,!0);if(void 0!==r&&!1!==r){n=r;break}}}else n="function"==typeof t.successor?t.successor({index:s,currentAxiom:this.axiom,part:i,params:o}):t.successor;return n||(e?n:i)},this.applyProductions=function(){let t="string"==typeof this.axiom?"":[],s=0;for(let i of this.axiom){let o=i.symbol||i,e=i.params||[],r=i;if(this.productions.has(o)){let t=this.productions.get(o);r=this.getProductionResult(t,s,i,e)}"string"==typeof t?t+=r:r instanceof Array?Array.prototype.push.apply(t,r):t.push(r),s++}return this.axiom=t,t},this.iterate=function(t=1){let s;this.iterations=t;for(let i=0;i<t;i++)s=this.applyProductions();return s},this.final=function(t){let s=0;for(let i of this.axiom){let o=i;if("object"==typeof i&&i.symbol&&(o=i.symbol),this.finals.has(o)){let e=this.finals.get(o),r=typeof e;if("function"!==r)throw Error("'"+o+"' has an object for a final function. But it is __not a function__ but a "+r+"!");e({index:s,part:i},t)}s++}},this.match=function({axiom_:t,match:s,ignoredSymbols:i,branchSymbols:o,index:e,direction:r}){let n=0,c=0;t=t||this.axiom,void 0===o&&(o=void 0!==this.branchSymbols?this.branchSymbols:[]),void 0===i&&(i=void 0!==this.ignoredSymbols?this.ignoredSymbols:[]);let a,h,l,u,f,d,m,g=[];if("right"===r){if(u=d=1,l=e+1,f=0,m=s.length,o.length>0){var y=o;a=y[0],h=y[1]}}else{if("left"!==r)throw Error(r,"is not a valid direction for matching.");if(u=d=-1,l=e-1,f=s.length-1,m=-1,o.length>0){var p=o;h=p[0],a=p[1]}}for(;l<t.length&&l>=0;l+=u){let o=t[l].symbol||t[l],e=s[f];if(o===e){if((0===n||c>0)&&(o===a?(c++,n++,f+=d):o===h?(c=Math.max(0,c-1),n=Math.max(0,n-1),0===c&&(f+=d)):(g.push(l),f+=d)),f===m)return{result:!0,matchIndices:g}}else if(o===a)n++,c>0&&c++;else if(o===h)n=Math.max(0,n-1),c>0&&(c=Math.max(0,c-1));else if((0===n||c>0&&e!==h)&&!1===i.includes(o))return{result:!1,matchIndices:g}}return{result:!1,matchIndices:g}},this.ignoredSymbols=c,this.debug=u,this.branchSymbols=r,this.allowClassicSyntax=a,this.classicParametricSyntax=h,this.forceObjects=l,this.setAxiom(t),this.clearProductions(),s&&this.setProductions(s),i&&this.setFinals(i),this}LSystem.transformClassicStochasticProductions=t,LSystem.transformClassicCSProduction=o,LSystem.transformClassicParametricAxiom=i,LSystem.testClassicParametricSyntax=s;export default LSystem;
+function t(t){return function(){let s=t,i=s.length,o=Math.random();for(let t=0;t<i;t++){if(o<=(t+1)/i)return s[t]}console.error("Should have returned a result of the list, something is wrong here with the random numbers?.")}}function s(t){return/\(.+\)/.test(t)}function i(t){let s=t.replace(/\s+/g,"").split(/[\(\)]/),i=[];for(let t=0;t<s.length-1;t+=2){let o=s[t+1].split(",").map(Number);i.push({symbol:s[t],params:o})}}function o(t){let s,i=t[0].match(/(.+)<(.)/),o=t[0].match(/(.)>(.+)/);if(null===i&&null===o)return t;let e=t[1].successor||t[1].successors?t[1]:{successor:t[1]};return null!==i&&(s=i[2],e.leftCtx=i[1]),null!==o&&(s=o[1],e.rightCtx=o[2]),[s,e]}function e(t){if("string"!=typeof t&&t instanceof String==!1)return t;let s=[];for(let i of t)s.push({symbol:i});return s}function r(t,s){if(t.hasOwnProperty("successors"))for(var i=0;i<t.successors.length;i++)t.successors[i]=r(t.successors[i],s);else!1===t.hasOwnProperty("successor")&&(t={successor:t});return s&&t.hasOwnProperty("successor")&&(t.successor=e(t.successor)),t}function n(t,s){return t[1]=r(t[1],s),t}function LSystem({axiom:t="",productions:s,finals:i,branchSymbols:r="[]",ignoredSymbols:c="+-&^/|\\",allowClassicSyntax:a=!0,classicParametricSyntax:h=!1,forceObjects:l=!1,debug:u=!1}){return this.setAxiom=function(t){this.axiom=this.forceObjects?e(t):t},this.getRaw=function(){return this.axiom},this.getString=function(t=!0){return"string"==typeof this.axiom?this.axiom:!0===t?this.axiom.reduce((t,s)=>{if(void 0===s.symbol)throw console.log("found:",s),new Error("L-Systems that use only objects as symbols (eg: {symbol: 'F', params: []}), cant use string symbols (eg. 'F')! Check if you always return objects in your productions and no strings.");return t+s.symbol},""):JSON.stringify(this.axiom)},this.getStringResult=this.getString,this.setProduction=function(t,s,i=!1){let e=[t,s];if(void 0===e)throw new Error("no production specified.");if(s.successor&&s.successors)throw new Error('You can not have both a "successor" and a "successors" field in your production!');if(!0===this.allowClassicSyntax&&(e=o(e)),(e=n(e,this.forceObjects))[1].isStochastic=void 0!==e[1].successors&&e[1].successors.every(t=>void 0!==t.weight),e[1].isStochastic){e[1].weightSum=0;for(let t of e[1].successors)e[1].weightSum+=t.weight}let r=e[0];if(!0===i&&this.productions.has(r)){let t=this.productions.get(r),s=t.successor,i=t.successors;s&&!i&&(t={successors:[t]}),t.successors.push(e[1]),this.productions.set(r,t)}else this.productions.set(r,e[1])},this.setProductions=function(t){if(void 0===t)throw new Error("no production specified.");this.clearProductions();for(let s of Object.entries(t)){let t=s[0],i=s[1];this.setProduction(t,i,!0)}},this.clearProductions=function(){this.productions=new Map},this.setFinal=function(t,s){let i=[t,s];if(void 0===i)throw new Error("no final specified.");this.finals.set(i[0],i[1])},this.setFinals=function(t){if(void 0===t)throw new Error("no finals specified.");this.finals=new Map;for(let s in t)t.hasOwnProperty(s)&&this.setFinal(s,t[s])},this.getProductionResult=function(t,s,i,o,e=!1){let n=void 0!==t.leftCtx||void 0!==t.rightCtx,a=!1,h=!0;if(void 0!==t.condition&&!1===t.condition({index:s,currentAxiom:this.axiom,part:i,params:o})?h=!1:n&&(void 0!==t.leftCtx&&void 0!==t.rightCtx?h=this.match({direction:"left",match:t.leftCtx,index:s,branchSymbols:r,ignoredSymbols:c}).result:void 0!==t.leftCtx?h=this.match({direction:"left",match:t.leftCtx,index:s,branchSymbols:r,ignoredSymbols:c}).result:void 0!==t.rightCtx&&(h=this.match({direction:"right",match:t.rightCtx,index:s,branchSymbols:r,ignoredSymbols:c}).result)),!1===h)a=!1;else if(t.successors){var l,u;t.isStochastic&&(u=Math.random()*t.weightSum,l=0);for(let e of t.successors){if(t.isStochastic&&(l+=e.weight)<u)continue;let r=this.getProductionResult(e,s,i,o,!0);if(void 0!==r&&!1!==r){a=r;break}}}else a="function"==typeof t.successor?t.successor({index:s,currentAxiom:this.axiom,part:i,params:o}):t.successor;return a||(e?a:i)},this.applyProductions=function(){let t="string"==typeof this.axiom?"":[],s=0;for(let i of this.axiom){let o=i.symbol||i,e=i.params||[],r=i;if(this.productions.has(o)){let t=this.productions.get(o);r=this.getProductionResult(t,s,i,e)}"string"==typeof t?t+=r:r instanceof Array?Array.prototype.push.apply(t,r):t.push(r),s++}return this.axiom=t,t},this.iterate=function(t=1){let s;this.iterations=t;for(let i=0;i<t;i++)s=this.applyProductions();return s},this.final=function(t){let s=0;for(let i of this.axiom){let o=i;if("object"==typeof i&&i.symbol&&(o=i.symbol),this.finals.has(o)){let e=this.finals.get(o),r=typeof e;if("function"!==r)throw Error("'"+o+"' has an object for a final function. But it is __not a function__ but a "+r+"!");e({index:s,part:i},t)}s++}},this.match=function({axiom_:t,match:s,ignoredSymbols:i,branchSymbols:o,index:e,direction:r}){let n=0,c=0;t=t||this.axiom,void 0===o&&(o=void 0!==this.branchSymbols?this.branchSymbols:[]),void 0===i&&(i=void 0!==this.ignoredSymbols?this.ignoredSymbols:[]);let a,h,l,u,f,d,m,g=[];if("right"===r){if(u=d=1,l=e+1,f=0,m=s.length,o.length>0){var y=o;a=y[0],h=y[1]}}else{if("left"!==r)throw Error(r,"is not a valid direction for matching.");if(u=d=-1,l=e-1,f=s.length-1,m=-1,o.length>0){var p=o;h=p[0],a=p[1]}}for(;l<t.length&&l>=0;l+=u){let o=t[l].symbol||t[l],e=s[f];if(o===e){if((0===n||c>0)&&(o===a?(c++,n++,f+=d):o===h?(c=Math.max(0,c-1),n=Math.max(0,n-1),0===c&&(f+=d)):(g.push(l),f+=d)),f===m)return{result:!0,matchIndices:g}}else if(o===a)n++,c>0&&c++;else if(o===h)n=Math.max(0,n-1),c>0&&(c=Math.max(0,c-1));else if((0===n||c>0&&e!==h)&&!1===i.includes(o))return{result:!1,matchIndices:g}}return{result:!1,matchIndices:g}},this.ignoredSymbols=c,this.debug=u,this.branchSymbols=r,this.allowClassicSyntax=a,this.classicParametricSyntax=h,this.forceObjects=l,this.setAxiom(t),this.clearProductions(),s&&this.setProductions(s),i&&this.setFinals(i),this}LSystem.transformClassicStochasticProductions=t,LSystem.transformClassicCSProduction=o,LSystem.transformClassicParametricAxiom=i,LSystem.testClassicParametricSyntax=s;export default LSystem;
diff --git a/dist/lindenmayer.js b/dist/lindenmayer.js
index e510e83..66f8949 100644
--- a/dist/lindenmayer.js
+++ b/dist/lindenmayer.js
@@ -126,7 +126,7 @@ function normalizeProduction(p, forceObjects) {
   return p;
 }
 
-function LSystem({ axiom = '', productions, finals, branchSymbols = '', ignoredSymbols = '', allowClassicSyntax = true, classicParametricSyntax = false, forceObjects = false, debug = false }) {
+function LSystem({ axiom = '', productions, finals, branchSymbols = '[]', ignoredSymbols = '+-&^/|\\', allowClassicSyntax = true, classicParametricSyntax = false, forceObjects = false, debug = false }) {
 
 	// TODO: forceObject to be more intelligent based on other productions??
 
@@ -166,7 +166,7 @@ function LSystem({ axiom = '', productions, finals, branchSymbols = '', ignoredS
 
 		// Apply production transformers and normalizations
 		if (this.allowClassicSyntax === true) {
-			newProduction = transformClassicCSProduction(newProduction, this.ignoredSymbols);
+			newProduction = transformClassicCSProduction(newProduction);
 		}
 
 		newProduction = normalizeProduction(newProduction, this.forceObjects);
@@ -252,11 +252,11 @@ function LSystem({ axiom = '', productions, finals, branchSymbols = '', ignoredS
 			precheck = false;
 		} else if (contextSensitive) {
 			if (p.leftCtx !== undefined && p.rightCtx !== undefined) {
-				precheck = this.match({ direction: 'left', match: p.leftCtx, index: index, branchSymbols: '[]' }).result && this.match({ direction: 'right', match: p.rightCtx, index: index, branchSymbols: '[]', ignoredSymbols: ignoredSymbols }).result;
+				precheck = this.match({ direction: 'left', match: p.leftCtx, index: index, branchSymbols, ignoredSymbols }).result;
 			} else if (p.leftCtx !== undefined) {
-				precheck = this.match({ direction: 'left', match: p.leftCtx, index: index, branchSymbols: '[]' }).result;
+				precheck = this.match({ direction: 'left', match: p.leftCtx, index: index, branchSymbols, ignoredSymbols }).result;
 			} else if (p.rightCtx !== undefined) {
-				precheck = this.match({ direction: 'right', match: p.rightCtx, index: index, branchSymbols: '[]' }).result;
+				precheck = this.match({ direction: 'right', match: p.rightCtx, index: index, branchSymbols, ignoredSymbols }).result;
 			}
 		}
 
diff --git a/dist/lindenmayer.min.js b/dist/lindenmayer.min.js
index b6de4ae..2ff3604 100644
--- a/dist/lindenmayer.min.js
+++ b/dist/lindenmayer.min.js
@@ -1 +1 @@
-"use strict";function t(t){return function(){let s=t,i=s.length,o=Math.random();for(let t=0;t<i;t++){if(o<=(t+1)/i)return s[t]}console.error("Should have returned a result of the list, something is wrong here with the random numbers?.")}}function s(t){return/\(.+\)/.test(t)}function i(t){let s=t.replace(/\s+/g,"").split(/[\(\)]/),i=[];for(let t=0;t<s.length-1;t+=2){let o=s[t+1].split(",").map(Number);i.push({symbol:s[t],params:o})}}function o(t){let s,i=t[0].match(/(.+)<(.)/),o=t[0].match(/(.)>(.+)/);if(null===i&&null===o)return t;let e=t[1].successor||t[1].successors?t[1]:{successor:t[1]};return null!==i&&(s=i[2],e.leftCtx=i[1]),null!==o&&(s=o[1],e.rightCtx=o[2]),[s,e]}function e(t){if("string"!=typeof t&&t instanceof String==!1)return t;let s=[];for(let i of t)s.push({symbol:i});return s}function r(t,s){if(t.hasOwnProperty("successors"))for(var i=0;i<t.successors.length;i++)t.successors[i]=r(t.successors[i],s);else!1===t.hasOwnProperty("successor")&&(t={successor:t});return s&&t.hasOwnProperty("successor")&&(t.successor=e(t.successor)),t}function n(t,s){return t[1]=r(t[1],s),t}function LSystem({axiom:t="",productions:s,finals:i,branchSymbols:r="",ignoredSymbols:c="",allowClassicSyntax:a=!0,classicParametricSyntax:h=!1,forceObjects:l=!1,debug:u=!1}){return this.setAxiom=function(t){this.axiom=this.forceObjects?e(t):t},this.getRaw=function(){return this.axiom},this.getString=function(t=!0){return"string"==typeof this.axiom?this.axiom:!0===t?this.axiom.reduce((t,s)=>{if(void 0===s.symbol)throw console.log("found:",s),new Error("L-Systems that use only objects as symbols (eg: {symbol: 'F', params: []}), cant use string symbols (eg. 'F')! Check if you always return objects in your productions and no strings.");return t+s.symbol},""):JSON.stringify(this.axiom)},this.getStringResult=this.getString,this.setProduction=function(t,s,i=!1){let e=[t,s];if(void 0===e)throw new Error("no production specified.");if(s.successor&&s.successors)throw new Error('You can not have both a "successor" and a "successors" field in your production!');if(!0===this.allowClassicSyntax&&(e=o(e,this.ignoredSymbols)),(e=n(e,this.forceObjects))[1].isStochastic=void 0!==e[1].successors&&e[1].successors.every(t=>void 0!==t.weight),e[1].isStochastic){e[1].weightSum=0;for(let t of e[1].successors)e[1].weightSum+=t.weight}let r=e[0];if(!0===i&&this.productions.has(r)){let t=this.productions.get(r),s=t.successor,i=t.successors;s&&!i&&(t={successors:[t]}),t.successors.push(e[1]),this.productions.set(r,t)}else this.productions.set(r,e[1])},this.setProductions=function(t){if(void 0===t)throw new Error("no production specified.");this.clearProductions();for(let s of Object.entries(t)){let t=s[0],i=s[1];this.setProduction(t,i,!0)}},this.clearProductions=function(){this.productions=new Map},this.setFinal=function(t,s){let i=[t,s];if(void 0===i)throw new Error("no final specified.");this.finals.set(i[0],i[1])},this.setFinals=function(t){if(void 0===t)throw new Error("no finals specified.");this.finals=new Map;for(let s in t)t.hasOwnProperty(s)&&this.setFinal(s,t[s])},this.getProductionResult=function(t,s,i,o,e=!1){let r=void 0!==t.leftCtx||void 0!==t.rightCtx,n=!1,a=!0;if(void 0!==t.condition&&!1===t.condition({index:s,currentAxiom:this.axiom,part:i,params:o})?a=!1:r&&(void 0!==t.leftCtx&&void 0!==t.rightCtx?a=this.match({direction:"left",match:t.leftCtx,index:s,branchSymbols:"[]"}).result&&this.match({direction:"right",match:t.rightCtx,index:s,branchSymbols:"[]",ignoredSymbols:c}).result:void 0!==t.leftCtx?a=this.match({direction:"left",match:t.leftCtx,index:s,branchSymbols:"[]"}).result:void 0!==t.rightCtx&&(a=this.match({direction:"right",match:t.rightCtx,index:s,branchSymbols:"[]"}).result)),!1===a)n=!1;else if(t.successors){var h,l;t.isStochastic&&(l=Math.random()*t.weightSum,h=0);for(let e of t.successors){if(t.isStochastic&&(h+=e.weight)<l)continue;let r=this.getProductionResult(e,s,i,o,!0);if(void 0!==r&&!1!==r){n=r;break}}}else n="function"==typeof t.successor?t.successor({index:s,currentAxiom:this.axiom,part:i,params:o}):t.successor;return n||(e?n:i)},this.applyProductions=function(){let t="string"==typeof this.axiom?"":[],s=0;for(let i of this.axiom){let o=i.symbol||i,e=i.params||[],r=i;if(this.productions.has(o)){let t=this.productions.get(o);r=this.getProductionResult(t,s,i,e)}"string"==typeof t?t+=r:r instanceof Array?Array.prototype.push.apply(t,r):t.push(r),s++}return this.axiom=t,t},this.iterate=function(t=1){let s;this.iterations=t;for(let i=0;i<t;i++)s=this.applyProductions();return s},this.final=function(t){let s=0;for(let i of this.axiom){let o=i;if("object"==typeof i&&i.symbol&&(o=i.symbol),this.finals.has(o)){let e=this.finals.get(o),r=typeof e;if("function"!==r)throw Error("'"+o+"' has an object for a final function. But it is __not a function__ but a "+r+"!");e({index:s,part:i},t)}s++}},this.match=function({axiom_:t,match:s,ignoredSymbols:i,branchSymbols:o,index:e,direction:r}){let n=0,c=0;t=t||this.axiom,void 0===o&&(o=void 0!==this.branchSymbols?this.branchSymbols:[]),void 0===i&&(i=void 0!==this.ignoredSymbols?this.ignoredSymbols:[]);let a,h,l,u,f,m,d,g=[];if("right"===r){if(u=m=1,l=e+1,f=0,d=s.length,o.length>0){var y=o;a=y[0],h=y[1]}}else{if("left"!==r)throw Error(r,"is not a valid direction for matching.");if(u=m=-1,l=e-1,f=s.length-1,d=-1,o.length>0){var p=o;h=p[0],a=p[1]}}for(;l<t.length&&l>=0;l+=u){let o=t[l].symbol||t[l],e=s[f];if(o===e){if((0===n||c>0)&&(o===a?(c++,n++,f+=m):o===h?(c=Math.max(0,c-1),n=Math.max(0,n-1),0===c&&(f+=m)):(g.push(l),f+=m)),f===d)return{result:!0,matchIndices:g}}else if(o===a)n++,c>0&&c++;else if(o===h)n=Math.max(0,n-1),c>0&&(c=Math.max(0,c-1));else if((0===n||c>0&&e!==h)&&!1===i.includes(o))return{result:!1,matchIndices:g}}return{result:!1,matchIndices:g}},this.ignoredSymbols=c,this.debug=u,this.branchSymbols=r,this.allowClassicSyntax=a,this.classicParametricSyntax=h,this.forceObjects=l,this.setAxiom(t),this.clearProductions(),s&&this.setProductions(s),i&&this.setFinals(i),this}LSystem.transformClassicStochasticProductions=t,LSystem.transformClassicCSProduction=o,LSystem.transformClassicParametricAxiom=i,LSystem.testClassicParametricSyntax=s,module.exports=LSystem;
+"use strict";function t(t){return function(){let s=t,i=s.length,o=Math.random();for(let t=0;t<i;t++){if(o<=(t+1)/i)return s[t]}console.error("Should have returned a result of the list, something is wrong here with the random numbers?.")}}function s(t){return/\(.+\)/.test(t)}function i(t){let s=t.replace(/\s+/g,"").split(/[\(\)]/),i=[];for(let t=0;t<s.length-1;t+=2){let o=s[t+1].split(",").map(Number);i.push({symbol:s[t],params:o})}}function o(t){let s,i=t[0].match(/(.+)<(.)/),o=t[0].match(/(.)>(.+)/);if(null===i&&null===o)return t;let e=t[1].successor||t[1].successors?t[1]:{successor:t[1]};return null!==i&&(s=i[2],e.leftCtx=i[1]),null!==o&&(s=o[1],e.rightCtx=o[2]),[s,e]}function e(t){if("string"!=typeof t&&t instanceof String==!1)return t;let s=[];for(let i of t)s.push({symbol:i});return s}function r(t,s){if(t.hasOwnProperty("successors"))for(var i=0;i<t.successors.length;i++)t.successors[i]=r(t.successors[i],s);else!1===t.hasOwnProperty("successor")&&(t={successor:t});return s&&t.hasOwnProperty("successor")&&(t.successor=e(t.successor)),t}function n(t,s){return t[1]=r(t[1],s),t}function LSystem({axiom:t="",productions:s,finals:i,branchSymbols:r="[]",ignoredSymbols:c="+-&^/|\\",allowClassicSyntax:a=!0,classicParametricSyntax:h=!1,forceObjects:l=!1,debug:u=!1}){return this.setAxiom=function(t){this.axiom=this.forceObjects?e(t):t},this.getRaw=function(){return this.axiom},this.getString=function(t=!0){return"string"==typeof this.axiom?this.axiom:!0===t?this.axiom.reduce((t,s)=>{if(void 0===s.symbol)throw console.log("found:",s),new Error("L-Systems that use only objects as symbols (eg: {symbol: 'F', params: []}), cant use string symbols (eg. 'F')! Check if you always return objects in your productions and no strings.");return t+s.symbol},""):JSON.stringify(this.axiom)},this.getStringResult=this.getString,this.setProduction=function(t,s,i=!1){let e=[t,s];if(void 0===e)throw new Error("no production specified.");if(s.successor&&s.successors)throw new Error('You can not have both a "successor" and a "successors" field in your production!');if(!0===this.allowClassicSyntax&&(e=o(e)),(e=n(e,this.forceObjects))[1].isStochastic=void 0!==e[1].successors&&e[1].successors.every(t=>void 0!==t.weight),e[1].isStochastic){e[1].weightSum=0;for(let t of e[1].successors)e[1].weightSum+=t.weight}let r=e[0];if(!0===i&&this.productions.has(r)){let t=this.productions.get(r),s=t.successor,i=t.successors;s&&!i&&(t={successors:[t]}),t.successors.push(e[1]),this.productions.set(r,t)}else this.productions.set(r,e[1])},this.setProductions=function(t){if(void 0===t)throw new Error("no production specified.");this.clearProductions();for(let s of Object.entries(t)){let t=s[0],i=s[1];this.setProduction(t,i,!0)}},this.clearProductions=function(){this.productions=new Map},this.setFinal=function(t,s){let i=[t,s];if(void 0===i)throw new Error("no final specified.");this.finals.set(i[0],i[1])},this.setFinals=function(t){if(void 0===t)throw new Error("no finals specified.");this.finals=new Map;for(let s in t)t.hasOwnProperty(s)&&this.setFinal(s,t[s])},this.getProductionResult=function(t,s,i,o,e=!1){let n=void 0!==t.leftCtx||void 0!==t.rightCtx,a=!1,h=!0;if(void 0!==t.condition&&!1===t.condition({index:s,currentAxiom:this.axiom,part:i,params:o})?h=!1:n&&(void 0!==t.leftCtx&&void 0!==t.rightCtx?h=this.match({direction:"left",match:t.leftCtx,index:s,branchSymbols:r,ignoredSymbols:c}).result:void 0!==t.leftCtx?h=this.match({direction:"left",match:t.leftCtx,index:s,branchSymbols:r,ignoredSymbols:c}).result:void 0!==t.rightCtx&&(h=this.match({direction:"right",match:t.rightCtx,index:s,branchSymbols:r,ignoredSymbols:c}).result)),!1===h)a=!1;else if(t.successors){var l,u;t.isStochastic&&(u=Math.random()*t.weightSum,l=0);for(let e of t.successors){if(t.isStochastic&&(l+=e.weight)<u)continue;let r=this.getProductionResult(e,s,i,o,!0);if(void 0!==r&&!1!==r){a=r;break}}}else a="function"==typeof t.successor?t.successor({index:s,currentAxiom:this.axiom,part:i,params:o}):t.successor;return a||(e?a:i)},this.applyProductions=function(){let t="string"==typeof this.axiom?"":[],s=0;for(let i of this.axiom){let o=i.symbol||i,e=i.params||[],r=i;if(this.productions.has(o)){let t=this.productions.get(o);r=this.getProductionResult(t,s,i,e)}"string"==typeof t?t+=r:r instanceof Array?Array.prototype.push.apply(t,r):t.push(r),s++}return this.axiom=t,t},this.iterate=function(t=1){let s;this.iterations=t;for(let i=0;i<t;i++)s=this.applyProductions();return s},this.final=function(t){let s=0;for(let i of this.axiom){let o=i;if("object"==typeof i&&i.symbol&&(o=i.symbol),this.finals.has(o)){let e=this.finals.get(o),r=typeof e;if("function"!==r)throw Error("'"+o+"' has an object for a final function. But it is __not a function__ but a "+r+"!");e({index:s,part:i},t)}s++}},this.match=function({axiom_:t,match:s,ignoredSymbols:i,branchSymbols:o,index:e,direction:r}){let n=0,c=0;t=t||this.axiom,void 0===o&&(o=void 0!==this.branchSymbols?this.branchSymbols:[]),void 0===i&&(i=void 0!==this.ignoredSymbols?this.ignoredSymbols:[]);let a,h,l,u,f,d,m,g=[];if("right"===r){if(u=d=1,l=e+1,f=0,m=s.length,o.length>0){var y=o;a=y[0],h=y[1]}}else{if("left"!==r)throw Error(r,"is not a valid direction for matching.");if(u=d=-1,l=e-1,f=s.length-1,m=-1,o.length>0){var p=o;h=p[0],a=p[1]}}for(;l<t.length&&l>=0;l+=u){let o=t[l].symbol||t[l],e=s[f];if(o===e){if((0===n||c>0)&&(o===a?(c++,n++,f+=d):o===h?(c=Math.max(0,c-1),n=Math.max(0,n-1),0===c&&(f+=d)):(g.push(l),f+=d)),f===m)return{result:!0,matchIndices:g}}else if(o===a)n++,c>0&&c++;else if(o===h)n=Math.max(0,n-1),c>0&&(c=Math.max(0,c-1));else if((0===n||c>0&&e!==h)&&!1===i.includes(o))return{result:!1,matchIndices:g}}return{result:!1,matchIndices:g}},this.ignoredSymbols=c,this.debug=u,this.branchSymbols=r,this.allowClassicSyntax=a,this.classicParametricSyntax=h,this.forceObjects=l,this.setAxiom(t),this.clearProductions(),s&&this.setProductions(s),i&&this.setFinals(i),this}LSystem.transformClassicStochasticProductions=t,LSystem.transformClassicCSProduction=o,LSystem.transformClassicParametricAxiom=i,LSystem.testClassicParametricSyntax=s,module.exports=LSystem;
diff --git a/docs/examples/lindenmayer.js b/docs/examples/lindenmayer.js
index c52e5ab..07e712c 100644
--- a/docs/examples/lindenmayer.js
+++ b/docs/examples/lindenmayer.js
@@ -1 +1 @@
-var LSystem=function(){"use strict";function t(t){let s,i=t[0].match(/(.+)<(.)/),o=t[0].match(/(.)>(.+)/);if(null===i&&null===o)return t;let e=t[1].successor||t[1].successors?t[1]:{successor:t[1]};return null!==i&&(s=i[2],e.leftCtx=i[1]),null!==o&&(s=o[1],e.rightCtx=o[2]),[s,e]}function s(t){if("string"!=typeof t&&t instanceof String==!1)return t;let s=[];for(let i of t)s.push({symbol:i});return s}function i(t,i){return t[1]=function t(i,o){if(i.hasOwnProperty("successors"))for(var e=0;e<i.successors.length;e++)i.successors[e]=t(i.successors[e],o);else!1===i.hasOwnProperty("successor")&&(i={successor:i});return o&&i.hasOwnProperty("successor")&&(i.successor=s(i.successor)),i}(t[1],i),t}function LSystem({axiom:o="",productions:e,finals:r,branchSymbols:n="",ignoredSymbols:c="",allowClassicSyntax:a=!0,classicParametricSyntax:h=!1,forceObjects:l=!1,debug:u=!1}){return this.setAxiom=function(t){this.axiom=this.forceObjects?s(t):t},this.getRaw=function(){return this.axiom},this.getString=function(t=!0){return"string"==typeof this.axiom?this.axiom:!0===t?this.axiom.reduce((t,s)=>{if(void 0===s.symbol)throw console.log("found:",s),new Error("L-Systems that use only objects as symbols (eg: {symbol: 'F', params: []}), cant use string symbols (eg. 'F')! Check if you always return objects in your productions and no strings.");return t+s.symbol},""):JSON.stringify(this.axiom)},this.getStringResult=this.getString,this.setProduction=function(s,o,e=!1){let r=[s,o];if(void 0===r)throw new Error("no production specified.");if(o.successor&&o.successors)throw new Error('You can not have both a "successor" and a "successors" field in your production!');if(!0===this.allowClassicSyntax&&(r=t(r,this.ignoredSymbols)),(r=i(r,this.forceObjects))[1].isStochastic=void 0!==r[1].successors&&r[1].successors.every(t=>void 0!==t.weight),r[1].isStochastic){r[1].weightSum=0;for(let t of r[1].successors)r[1].weightSum+=t.weight}let n=r[0];if(!0===e&&this.productions.has(n)){let t=this.productions.get(n),s=t.successor,i=t.successors;s&&!i&&(t={successors:[t]}),t.successors.push(r[1]),this.productions.set(n,t)}else this.productions.set(n,r[1])},this.setProductions=function(t){if(void 0===t)throw new Error("no production specified.");this.clearProductions();for(let s of Object.entries(t)){let t=s[0],i=s[1];this.setProduction(t,i,!0)}},this.clearProductions=function(){this.productions=new Map},this.setFinal=function(t,s){let i=[t,s];if(void 0===i)throw new Error("no final specified.");this.finals.set(i[0],i[1])},this.setFinals=function(t){if(void 0===t)throw new Error("no finals specified.");this.finals=new Map;for(let s in t)t.hasOwnProperty(s)&&this.setFinal(s,t[s])},this.getProductionResult=function(t,s,i,o,e=!1){let r=void 0!==t.leftCtx||void 0!==t.rightCtx,n=!1,a=!0;if(void 0!==t.condition&&!1===t.condition({index:s,currentAxiom:this.axiom,part:i,params:o})?a=!1:r&&(void 0!==t.leftCtx&&void 0!==t.rightCtx?a=this.match({direction:"left",match:t.leftCtx,index:s,branchSymbols:"[]"}).result&&this.match({direction:"right",match:t.rightCtx,index:s,branchSymbols:"[]",ignoredSymbols:c}).result:void 0!==t.leftCtx?a=this.match({direction:"left",match:t.leftCtx,index:s,branchSymbols:"[]"}).result:void 0!==t.rightCtx&&(a=this.match({direction:"right",match:t.rightCtx,index:s,branchSymbols:"[]"}).result)),!1===a)n=!1;else if(t.successors){var h,l;t.isStochastic&&(l=Math.random()*t.weightSum,h=0);for(let e of t.successors){if(t.isStochastic&&(h+=e.weight)<l)continue;let r=this.getProductionResult(e,s,i,o,!0);if(void 0!==r&&!1!==r){n=r;break}}}else n="function"==typeof t.successor?t.successor({index:s,currentAxiom:this.axiom,part:i,params:o}):t.successor;return n||(e?n:i)},this.applyProductions=function(){let t="string"==typeof this.axiom?"":[],s=0;for(let i of this.axiom){let o=i.symbol||i,e=i.params||[],r=i;if(this.productions.has(o)){let t=this.productions.get(o);r=this.getProductionResult(t,s,i,e)}"string"==typeof t?t+=r:r instanceof Array?Array.prototype.push.apply(t,r):t.push(r),s++}return this.axiom=t,t},this.iterate=function(t=1){let s;this.iterations=t;for(let i=0;i<t;i++)s=this.applyProductions();return s},this.final=function(t){let s=0;for(let i of this.axiom){let o=i;if("object"==typeof i&&i.symbol&&(o=i.symbol),this.finals.has(o)){let e=this.finals.get(o),r=typeof e;if("function"!==r)throw Error("'"+o+"' has an object for a final function. But it is __not a function__ but a "+r+"!");e({index:s,part:i},t)}s++}},this.match=function({axiom_:t,match:s,ignoredSymbols:i,branchSymbols:o,index:e,direction:r}){let n=0,c=0;t=t||this.axiom,void 0===o&&(o=void 0!==this.branchSymbols?this.branchSymbols:[]),void 0===i&&(i=void 0!==this.ignoredSymbols?this.ignoredSymbols:[]);let a,h,l,u,f,m,d,g=[];if("right"===r){if(u=m=1,l=e+1,f=0,d=s.length,o.length>0){var y=o;a=y[0],h=y[1]}}else{if("left"!==r)throw Error(r,"is not a valid direction for matching.");if(u=m=-1,l=e-1,f=s.length-1,d=-1,o.length>0){var p=o;h=p[0],a=p[1]}}for(;l<t.length&&l>=0;l+=u){let o=t[l].symbol||t[l],e=s[f];if(o===e){if((0===n||c>0)&&(o===a?(c++,n++,f+=m):o===h?(c=Math.max(0,c-1),n=Math.max(0,n-1),0===c&&(f+=m)):(g.push(l),f+=m)),f===d)return{result:!0,matchIndices:g}}else if(o===a)n++,c>0&&c++;else if(o===h)n=Math.max(0,n-1),c>0&&(c=Math.max(0,c-1));else if((0===n||c>0&&e!==h)&&!1===i.includes(o))return{result:!1,matchIndices:g}}return{result:!1,matchIndices:g}},this.ignoredSymbols=c,this.debug=u,this.branchSymbols=n,this.allowClassicSyntax=a,this.classicParametricSyntax=h,this.forceObjects=l,this.setAxiom(o),this.clearProductions(),e&&this.setProductions(e),r&&this.setFinals(r),this}return LSystem.transformClassicStochasticProductions=function(t){return function(){let s=t,i=s.length,o=Math.random();for(let t=0;t<i;t++)if(o<=(t+1)/i)return s[t];console.error("Should have returned a result of the list, something is wrong here with the random numbers?.")}},LSystem.transformClassicCSProduction=t,LSystem.transformClassicParametricAxiom=function(t){let s=t.replace(/\s+/g,"").split(/[\(\)]/),i=[];for(let t=0;t<s.length-1;t+=2){let o=s[t+1].split(",").map(Number);i.push({symbol:s[t],params:o})}},LSystem.testClassicParametricSyntax=function(t){return/\(.+\)/.test(t)},LSystem}();
+var LSystem=function(){"use strict";function t(t){let s,i=t[0].match(/(.+)<(.)/),o=t[0].match(/(.)>(.+)/);if(null===i&&null===o)return t;let e=t[1].successor||t[1].successors?t[1]:{successor:t[1]};return null!==i&&(s=i[2],e.leftCtx=i[1]),null!==o&&(s=o[1],e.rightCtx=o[2]),[s,e]}function s(t){if("string"!=typeof t&&t instanceof String==!1)return t;let s=[];for(let i of t)s.push({symbol:i});return s}function i(t,i){return t[1]=function t(i,o){if(i.hasOwnProperty("successors"))for(var e=0;e<i.successors.length;e++)i.successors[e]=t(i.successors[e],o);else!1===i.hasOwnProperty("successor")&&(i={successor:i});return o&&i.hasOwnProperty("successor")&&(i.successor=s(i.successor)),i}(t[1],i),t}function LSystem({axiom:o="",productions:e,finals:r,branchSymbols:n="[]",ignoredSymbols:c="+-&^/|\\",allowClassicSyntax:a=!0,classicParametricSyntax:h=!1,forceObjects:l=!1,debug:u=!1}){return this.setAxiom=function(t){this.axiom=this.forceObjects?s(t):t},this.getRaw=function(){return this.axiom},this.getString=function(t=!0){return"string"==typeof this.axiom?this.axiom:!0===t?this.axiom.reduce((t,s)=>{if(void 0===s.symbol)throw console.log("found:",s),new Error("L-Systems that use only objects as symbols (eg: {symbol: 'F', params: []}), cant use string symbols (eg. 'F')! Check if you always return objects in your productions and no strings.");return t+s.symbol},""):JSON.stringify(this.axiom)},this.getStringResult=this.getString,this.setProduction=function(s,o,e=!1){let r=[s,o];if(void 0===r)throw new Error("no production specified.");if(o.successor&&o.successors)throw new Error('You can not have both a "successor" and a "successors" field in your production!');if(!0===this.allowClassicSyntax&&(r=t(r)),(r=i(r,this.forceObjects))[1].isStochastic=void 0!==r[1].successors&&r[1].successors.every(t=>void 0!==t.weight),r[1].isStochastic){r[1].weightSum=0;for(let t of r[1].successors)r[1].weightSum+=t.weight}let n=r[0];if(!0===e&&this.productions.has(n)){let t=this.productions.get(n),s=t.successor,i=t.successors;s&&!i&&(t={successors:[t]}),t.successors.push(r[1]),this.productions.set(n,t)}else this.productions.set(n,r[1])},this.setProductions=function(t){if(void 0===t)throw new Error("no production specified.");this.clearProductions();for(let s of Object.entries(t)){let t=s[0],i=s[1];this.setProduction(t,i,!0)}},this.clearProductions=function(){this.productions=new Map},this.setFinal=function(t,s){let i=[t,s];if(void 0===i)throw new Error("no final specified.");this.finals.set(i[0],i[1])},this.setFinals=function(t){if(void 0===t)throw new Error("no finals specified.");this.finals=new Map;for(let s in t)t.hasOwnProperty(s)&&this.setFinal(s,t[s])},this.getProductionResult=function(t,s,i,o,e=!1){let r=void 0!==t.leftCtx||void 0!==t.rightCtx,a=!1,h=!0;if(void 0!==t.condition&&!1===t.condition({index:s,currentAxiom:this.axiom,part:i,params:o})?h=!1:r&&(void 0!==t.leftCtx&&void 0!==t.rightCtx?h=this.match({direction:"left",match:t.leftCtx,index:s,branchSymbols:n,ignoredSymbols:c}).result:void 0!==t.leftCtx?h=this.match({direction:"left",match:t.leftCtx,index:s,branchSymbols:n,ignoredSymbols:c}).result:void 0!==t.rightCtx&&(h=this.match({direction:"right",match:t.rightCtx,index:s,branchSymbols:n,ignoredSymbols:c}).result)),!1===h)a=!1;else if(t.successors){var l,u;t.isStochastic&&(u=Math.random()*t.weightSum,l=0);for(let e of t.successors){if(t.isStochastic&&(l+=e.weight)<u)continue;let r=this.getProductionResult(e,s,i,o,!0);if(void 0!==r&&!1!==r){a=r;break}}}else a="function"==typeof t.successor?t.successor({index:s,currentAxiom:this.axiom,part:i,params:o}):t.successor;return a||(e?a:i)},this.applyProductions=function(){let t="string"==typeof this.axiom?"":[],s=0;for(let i of this.axiom){let o=i.symbol||i,e=i.params||[],r=i;if(this.productions.has(o)){let t=this.productions.get(o);r=this.getProductionResult(t,s,i,e)}"string"==typeof t?t+=r:r instanceof Array?Array.prototype.push.apply(t,r):t.push(r),s++}return this.axiom=t,t},this.iterate=function(t=1){let s;this.iterations=t;for(let i=0;i<t;i++)s=this.applyProductions();return s},this.final=function(t){let s=0;for(let i of this.axiom){let o=i;if("object"==typeof i&&i.symbol&&(o=i.symbol),this.finals.has(o)){let e=this.finals.get(o),r=typeof e;if("function"!==r)throw Error("'"+o+"' has an object for a final function. But it is __not a function__ but a "+r+"!");e({index:s,part:i},t)}s++}},this.match=function({axiom_:t,match:s,ignoredSymbols:i,branchSymbols:o,index:e,direction:r}){let n=0,c=0;t=t||this.axiom,void 0===o&&(o=void 0!==this.branchSymbols?this.branchSymbols:[]),void 0===i&&(i=void 0!==this.ignoredSymbols?this.ignoredSymbols:[]);let a,h,l,u,f,d,m,g=[];if("right"===r){if(u=d=1,l=e+1,f=0,m=s.length,o.length>0){var y=o;a=y[0],h=y[1]}}else{if("left"!==r)throw Error(r,"is not a valid direction for matching.");if(u=d=-1,l=e-1,f=s.length-1,m=-1,o.length>0){var p=o;h=p[0],a=p[1]}}for(;l<t.length&&l>=0;l+=u){let o=t[l].symbol||t[l],e=s[f];if(o===e){if((0===n||c>0)&&(o===a?(c++,n++,f+=d):o===h?(c=Math.max(0,c-1),n=Math.max(0,n-1),0===c&&(f+=d)):(g.push(l),f+=d)),f===m)return{result:!0,matchIndices:g}}else if(o===a)n++,c>0&&c++;else if(o===h)n=Math.max(0,n-1),c>0&&(c=Math.max(0,c-1));else if((0===n||c>0&&e!==h)&&!1===i.includes(o))return{result:!1,matchIndices:g}}return{result:!1,matchIndices:g}},this.ignoredSymbols=c,this.debug=u,this.branchSymbols=n,this.allowClassicSyntax=a,this.classicParametricSyntax=h,this.forceObjects=l,this.setAxiom(o),this.clearProductions(),e&&this.setProductions(e),r&&this.setFinals(r),this}return LSystem.transformClassicStochasticProductions=function(t){return function(){let s=t,i=s.length,o=Math.random();for(let t=0;t<i;t++)if(o<=(t+1)/i)return s[t];console.error("Should have returned a result of the list, something is wrong here with the random numbers?.")}},LSystem.transformClassicCSProduction=t,LSystem.transformClassicParametricAxiom=function(t){let s=t.replace(/\s+/g,"").split(/[\(\)]/),i=[];for(let t=0;t<s.length-1;t+=2){let o=s[t+1].split(",").map(Number);i.push({symbol:s[t],params:o})}},LSystem.testClassicParametricSyntax=function(t){return/\(.+\)/.test(t)},LSystem}();
diff --git a/lindenmayer.js b/lindenmayer.js
index 3607156..0515de5 100644
--- a/lindenmayer.js
+++ b/lindenmayer.js
@@ -3,7 +3,7 @@
 import {transformClassicStochasticProductions, transformClassicCSProduction, transformClassicParametricAxiom, testClassicParametricSyntax} from './transformersClassicSyntax';
 import {stringToObjects, normalizeProduction} from './transformers.js';
 
-export default function LSystem({axiom = '', productions, finals, branchSymbols='', ignoredSymbols='', allowClassicSyntax=true, classicParametricSyntax=false, forceObjects=false, debug=false}) {
+export default function LSystem({axiom = '', productions, finals, branchSymbols='[]', ignoredSymbols='+-&^/|\\', allowClassicSyntax=true, classicParametricSyntax=false, forceObjects=false, debug=false}) {
 
 
 // TODO: forceObject to be more intelligent based on other productions??
@@ -50,7 +50,7 @@ export default function LSystem({axiom = '', productions, finals, branchSymbols=
 
 		// Apply production transformers and normalizations
 		if(this.allowClassicSyntax === true) {
-			newProduction = transformClassicCSProduction(newProduction, this.ignoredSymbols);
+			newProduction = transformClassicCSProduction(newProduction);
 		}
 
 		newProduction = normalizeProduction(newProduction, this.forceObjects);
@@ -140,11 +140,11 @@ export default function LSystem({axiom = '', productions, finals, branchSymbols=
 		}
 		else if(contextSensitive) {
 			if(p.leftCtx !== undefined && p.rightCtx !== undefined){
-				precheck = this.match({direction: 'left', match: p.leftCtx, index: index, branchSymbols: '[]'}).result && this.match({direction: 'right', match: p.rightCtx, index: index, branchSymbols: '[]', ignoredSymbols: ignoredSymbols}).result;
+				precheck = this.match({direction: 'left', match: p.leftCtx, index: index, branchSymbols, ignoredSymbols}).result;
 			} else if (p.leftCtx !== undefined) {
-				precheck = this.match({direction: 'left', match: p.leftCtx, index: index, branchSymbols: '[]'}).result;
+				precheck = this.match({direction: 'left', match: p.leftCtx, index: index, branchSymbols, ignoredSymbols}).result;
 			} else if (p.rightCtx !== undefined) {
-				precheck = this.match({direction: 'right', match: p.rightCtx, index: index, branchSymbols: '[]'}).result;
+				precheck = this.match({direction: 'right', match: p.rightCtx, index: index, branchSymbols, ignoredSymbols}).result;
 			}
 
 		}
diff --git a/package.json b/package.json
index 7b13645..e6e3f80 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "lindenmayer",
   "description": "Lindenmayer is  a L-System/LSystem library using modern (ES6) JavaScript with focus on a concise syntax. The idea is to have a very powerful but simple base functionality, that can handle most use-cases by simply allowing anonymous functions as productions, which makes it very flexible in comparison to classic L-Systems.",
-  "version": "1.3.7",
+  "version": "1.4.0",
   "author": "Tom Brewe <info@nylkiway.net>",
   "license": "MIT",
   "keywords": [
diff --git a/test/tests.js b/test/tests.js
index 84ef01c..3b50fa5 100644
--- a/test/tests.js
+++ b/test/tests.js
@@ -48,7 +48,7 @@ describe('Basic String based L-Systems', function() {
 
 
 
-describe('String based L-Systems with additional context-sensitive classic ABOP syntax productions', function() {
+describe('String based L-Systems with additional context-sensitive classic ABOP syntax productions:', function() {
 
 it('Classic context sensitive syntax should work.', function() {
     let cs_LSystem7 = new LSystem({
@@ -72,15 +72,24 @@ it('Classic context sensitive syntax should work.', function() {
   });
 
 
-  it('Left side, classic CS should work.', function() {
-    let cs_LSystem8 = new LSystem({
+  it('Left side, classic CS should work with default ignored symbols.', function() {
+    let cs_LSystem8a = new LSystem({
+      axiom: 'A+B+C[DE][-S-G[HI[JK]L-]M-NO]',
+      productions: {'BC<S': 'Z'}
+    });
+    expect(cs_LSystem8a.iterate()).to.equal('A+B+C[DE][-Z-G[HI[JK]L-]M-NO]');
+  });
+  
+  it('Left side, classic CS should work with explitly set ignored symbols.', function() {
+    let cs_LSystem8b = new LSystem({
       axiom: 'A+B+C[DE][-S-G[HI[JK]L-]M-NO]',
       productions: {'BC<S': 'Z'},
       ignoredSymbols: '+-'
     });
-    expect(cs_LSystem8.iterate()).to.equal('A+B+C[DE][-Z-G[HI[JK]L-]M-NO]');
+    expect(cs_LSystem8b.iterate()).to.equal('A+B+C[DE][-Z-G[HI[JK]L-]M-NO]');
   });
 
+
   it('multiple CS production on the same base symbol should work.', function () {
     // ATTENTION: Objecert order is not preserved in JS Objects
     // If you want to rely on the order you define productions
@@ -105,13 +114,23 @@ it('Classic context sensitive syntax should work.', function() {
 
 
 
-  it('right side, classic CS should work.', function() {
-    let cs_LSystem8 = new LSystem({
-      axiom: 'ABC[DE][SG[HI[JK]L]MNO]',
-      productions: {'S>G[H]M': 'Z'}
+  it('Right side, classic CS should work with default ignored symbols.', function() {
+    let cs_LSystem8a = new LSystem({
+      axiom: 'A+B+C[DE][-S-G[HI[JK]L-]M-NO]',
+      productions: {'S>GM': 'Z'}
     });
-    expect(cs_LSystem8.iterate()).to.equal('ABC[DE][ZG[HI[JK]L]MNO]');
+    expect(cs_LSystem8a.iterate()).to.equal('A+B+C[DE][-Z-G[HI[JK]L-]M-NO]');
   });
+  
+  it('Right side, classic CS should work with explitly set ignored symbols.', function() {
+    let cs_LSystem8b = new LSystem({
+      axiom: 'A+B+C[DE][-S-G[HI[JK]L-]M-NO]',
+      productions: {'S>GM': 'Z'},
+      ignoredSymbols: '+-'
+    });
+    expect(cs_LSystem8b.iterate()).to.equal('A+B+C[DE][-Z-G[HI[JK]L-]M-NO]');
+  });
+
 
 });