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Writing a Scripting Language

One of the projects that I am working on is how to write a scripting language using c++.  At first thought, I imagined the task to be hard, but to my surprise it is quiet easy.

In this post I will introduce the basics.  However, I do suggest you visit my youtube channel and watch the video series.

expression, token, compile, c, script, c++, write, programming
token evaluation process
 As you can see from the image to the left, my script engine basically takes a string expression, converts it to tokens, determines its meaning, and then compiles the effective byte code.

Byte code is the instruction set for my script language.  It will tell our virtual machine or virtual process what an instruction is suppose to do.






recursive, call, token, script, evaluation, process, programming
In more detail, the script engine does a recursive call with the tokens to successfully generate all the corresponding byte code.


Source Code

This link contains the source code and is version 1 of script.
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Comments

  1. UnknownApril 23, 2015 at 7:50 AM

    Hello,

    I have a little problem.
    When I use s.execute("equation(1,2)"); It just keeps printing the message over and over again.
    Can you help me?

    ReplyDelete
  2. UnknownJune 5, 2018 at 6:02 AM


    but if(var1=var2) and else don't work how can I solve it?

    ReplyDelete

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