Compiler Visualizations

Source

let
    function readline():string =
        /* strips leading spaces */
        let
            var ret:string := ""
            var buffer := getchar()
        in
            (while buffer = " " do
                buffer := getchar();
            while buffer <> "\n" do
                (ret := concat(ret, buffer);
                buffer := getchar());
            ret)
        end

    class Person extends Object {
        var name:string := "anonymous"
        method init() =
            (print("What is your name: ");
            name := readline())
    }

    var you := new Person
in
    you.init();
    print("hello, ");
    print(you.name);
    print("\n")
end

Input   

State    initial

Tokens

LET FUNCTION ID "readline" LPAREN RPAREN COLON ID "string" EQ LET VAR ID "ret" COLON ID "string" ASSIGN STRING "" VAR ID "buffer" ASSIGN ID "getchar" LPAREN RPAREN IN LPAREN WHILE ID "buffer" EQ STRING "" DO ID "buffer" ASSIGN ID "getchar" LPAREN RPAREN SEMICOLON WHILE ID "buffer" NEQ STRING "" DO LPAREN ID "ret" ASSIGN ID "concat" LPAREN ID "ret" COMMA ID "buffer" RPAREN SEMICOLON ID "buffer" ASSIGN ID "getchar" LPAREN RPAREN RPAREN SEMICOLON ID "ret" RPAREN END CLASS ID "Person" EXTENDS ID "Object" LBRACE VAR ID "name" COLON ID "string" ASSIGN STRING "" METHOD ID "init" LPAREN RPAREN EQ LPAREN ID "print" LPAREN STRING "" RPAREN SEMICOLON ID "name" ASSIGN ID "readline" LPAREN RPAREN RPAREN RBRACE VAR ID "you" ASSIGN NEW ID "Person" IN ID "you" DOT ID "init" LPAREN RPAREN SEMICOLON ID "print" LPAREN STRING "" RPAREN SEMICOLON ID "print" LPAREN ID "you" DOT ID "name" RPAREN SEMICOLON ID "print" LPAREN STRING "" RPAREN END