java - ANTLR4 JavaScript Target very slow -


i'm developing antlr4 javascript listener grammar. 

    var _require = require;     var antlr = _require('./antlr4/index');     var javalexer = _require('./generated/javalexer');     var javaparser = _require('./generated/javaparser');     var javalistener = _require('./generated/javalistener');      declare function require(name:string);        class codeanalysis {          input: string;          constructor(input:string) {           this.input = input;           this.antlrstack();         }      private antlrstack() {       console.log(this.input);       var chars = new antlr.inputstream(this.input);       var lexer = new javalexer.javalexer(chars);       var tokens = new antlr.commontokenstream(lexer);       var parser = new javaparser.javaparser(tokens);       var listener = new javalistener.javalistener();       parser.buildparsetrees = true;       var tree = parser.compilationunit();         antlr.tree.parsetreewalker.default.walk(listener, tree);     }      public getinput() {     return this.input;     }      }

the problem performance bad (takes on 2 min) input this:

import codescape.dogbot; public class mydogbot extends dogbot{    public void run() {      turnleft();     move();    } }

the same grammar , same listener in java performs lot faster (>2 sec).

anybody idea why? or how fix it?

bruno

the honest truth may javascript slower language....you view analytics tools in chrome or other browser , see if there bottlenecks in antlr runtime or own few lines of code chances more javascript engine performance javascript entirely text , java compiled bytecode , run lower level using virtual machine, means bytecode executed perform faster interpretation of bytecode machine code extremely fast whilst javascript has interpreted line line executed.


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