interpreter

How is IO monad actually implemented?in sense of, what would be the actual implementation of the main function? How would I call haskell function (IO) from another language and do I in that case need to maintain IO my self? Does main pulls IO actions (Lazily) as references and then call them? Or it is interpreter job, when it found actions in its way it can call them? Or maybe something else? Is there good IO monad implementation in different language which can help to deeply understand what happening in main function? Edit: Such hGetContents confuses me a lot, and makes me unsure how IO is

"There is no such thing as a "compiled language" or "interpreted language". Whether a language implementer chooses to write a compiler, an interpreter or anything in between is an implementation detail and has nothing to do with the language. " Is the above statement is true ? Yes, it is true in the strictest interpretation. You can find both a C++ interpreter and a Javascript compiler , for example. However, you will find that some types of languages (statically typed, for example) lend themselves well to native code compilation. Other languages (dynamically typed, for example) are commonly

I am attempting to build an educational coding site, similar to Codecademy , but I am frankly at a loss as to what steps should be taken. Could I be pointed in the right direction in including even a simple python interpreter in a webapp? One option might be to use PyPy to create a sandboxed python. It would limit the external operations someone could do. Once you have that set up, your website would take the code source, send it over ajax to your webserver, and the server would run the code in a subprocess of a sandboxed python instance. You would also be able to kill the process if it took

/bin/sh^M: bad interpreter:没有那个文件或目录解决 执行脚本时发现如下错误： /bin/sh^M: bad interpreter: 没有那个文件或目录 错误分析: 因为操作系统是windows，我在windows下编辑的脚本，所以有可能有不可见字符。 脚本文件是DOS格式的, 即每一行的行尾以\n\r来标识, 其ASCII码分别是0x0D, 0x0A. 可以有很多种办法看这个文件是DOS格式的还是UNIX格式的, 还是MAC格式的 解决方法： vim filename 然后用命令 :set ff? #可以看到dos或unix的字样. 如果的确是dos格式的。 然后用 :set ff=unix #把它强制为unix格式的, 然后存盘退出。 再次运行脚本。 另外一种解决方法是使用dos2unix命令转一下，即输入： dos2unix 文件名 来源： oschina 链接： https://my.oschina.net/u/160700/blog/206162

I'm going through SICP and I'd like to have an interpreter analogous to the interactive Python interpreter to play around in while I'm watching the lectures and reading the book. Furthermore, I'd like this interpreter to run inside Emacs so I can jump back and forth between files of scheme code and the interactive interpreter and so forth. However, I'm fairly new to Emacs and have not as of yet been able to get this to work or find one clear set of instructions to use in getting it to work. It seems like I should be able to set it up so that M-x run-scheme will open up an interactive

I'm interested in implementing a Forth system, just so I can get some experience building a simple VM and runtime. When starting in Forth, one typically learns about the stack and its operators (DROP, DUP, SWAP, etc.) first, so it's natural to think of these as being among the primitive operators. But they're not. Each of them can be broken down into operators that directly manipulate memory and the stack pointers. Later one learns about store (!) and fetch (@) which can be used to implement DUP, SWAP, and so forth (ha!). So what are the primitive operators? Which ones must be implemented

Several months ago, I wrote a blog post detailing how to achieve tab-completion in the standard Python interactive interpreter--a feature I once thought only available in IPython. I've found it tremendously handy given that I sometimes have to switch to the standard interpreter due to IPython unicode issues. Recently I've done some work in OS X. To my discontent, the script doesn't seem to work for OS X's Terminal application. I'm hoping some of you with experience in OS X might be able to help me trouble-shoot it so it can work in Terminal, as well. I am reproducing the code below import

I have decided to write a small interpreter as my next project, in Ruby. What knowledge/skills will I need to have to be successful? I haven't decided on the language to interpret yet, but I am looking for something that is not a toy language, but would be relatively easy to write an interpreter for. Thanks in advance. You will have to learn at least: lexical analysis (grouping characters into tokens) parsing (grouping tokens together into structure) abstract syntax trees (representing program structure in a data structure) data representation (assuming your language will have variables) an

Is there an online interpreter like http://codepad.org/ or http://www.trypython.org/ which uses Python 3? Answer Since the question is closed, I give another answer here. Wandbox offers online REPLs for many languages, including Python 2.x and 3.x, C++ and Java. Ideone supports Python 2.6 and Python 3 I recently came across Python 3 interpreter at CompileOnline . 来源： https://stackoverflow.com/questions/2737539/python-3-online-interpreter-shell