How to efficently build an interpreter (lexer+parser) in C?
- by Rizo
I'm trying to make a meta-language for writing markup code (such as xml and html) wich can be directly embedded into C/C++ code.
Here is a simple sample written in this language, I call it WDI (Web Development Interface):
/*
* Simple wdi/html sample source code
*/
#include <mySite>
string name = "myName";
string toCapital(string str);
html
{
head {
title { mySiteTitle; }
link(rel="stylesheet", href="style.css");
}
body(id="default") {
// Page content wrapper
div(id="wrapper", class="some_class") {
h1 { "Hello, " + toCapital(name) + "!"; }
// Lists post
ul(id="post_list") {
for(post in posts) {
li { a(href=post.getID()) { post.tilte; } }
}
}
}
}
}
Basically it is a C source with a user-friendly interface for html.
As you can see the traditional tag-based style is substituted by C-like, with blocks delimited by curly braces.
I need to build an interpreter to translate this code to html and posteriorly insert it into C, so that it can be compiled. The C part stays intact.
Inside the wdi source it is not necessary to use prints, every return statement will be used for output (in printf function).
The program's output will be clean html code.
So, for example a heading 1 tag would be transformed like this:
h1 { "Hello, " + toCapital(name) + "!"; }
// would become:
printf("<h1>Hello, %s!</h1>", toCapital(name));
My main goal is to create an interpreter to translate wdi source to html like this:
tag(attributes) {content} = <tag attributes>content</tag>
Secondly, html code returned by the interpreter has to be inserted into C code with printfs. Variables and functions that occur inside wdi should also be sorted in order to use them as printf parameters (the case of toCapital(name) in sample source).
I am searching for efficient (I want to create a fast parser) way to create a lexer and parser for wdi. Already tried flex and bison, but as I am not sure if they are the best tools. Are there any good alternatives? What is the best way to create such an interpreter? Can you advise some brief literature on this issue?
