code: function highlightText(unhighlightedCode, languageId, partialContext) {
  			var language = languages[languageId],
  				analyzerContext;
  			
  			partialContext = partialContext || { };
  			if (language === undefined) {
  				//use default language if one wasn't specified or hasn't been registered
  				language = languages[DEFAULT_LANGUAGE];
  			}
  
  			fireEvent("beforeHighlight", this, { code: unhighlightedCode, language: language, previousContext: partialContext });
  			
  			analyzerContext = createAnalyzerContext(
  				tokenize.call(this, unhighlightedCode, language, partialContext, this.options),
  				partialContext,
  				this.options
  			);
  			
  			analyze.call(this, analyzerContext, partialContext.index ? partialContext.index + 1 : 0);
  			
  			fireEvent("afterHighlight", this, { analyzerContext: analyzerContext });
  
  			return analyzerContext;
  		}
docs: partialContext allows us to perform a partial parse, and then pick up where we left off at a later time this functionality enables nested highlights (language within a language, e.g. PHP within HTML followed by more PHP)