Subj : Parser generators for a simple language form. How?
To   : comp.programming
From : Jon Ripley
Date : Tue Aug 02 2005 07:33 pm

This has been bugging me for a while and I'd appreciate some input.

I have a number of simple scripting languages of similiar specifications 
that I use for rapid application development that I would like to make 
available to a wider audience. The wider audience use whichever 
operating system they want to on whatever platform they purchased.

Currently they are all implemented in a non-portable language and whilst 
they suit my current needs perfectly they are of limited use to others 
and need to be recoded in a portable language to be compiled for 
whatever OS/platform any given user may want to use them on. My first 
choice for the portable language is C and these will all be command line 
tools.

I would like to use a tool to generate the parser for each language, 
generally the only difference in the languages are the names of the 
functions and the parameters that they take. The format looks similiar 
to the C language - I decided that this would be the most transparent to 
  the largest number of users.

The general format is as follows:

/* Multiline comment */
mylang( <number> )
{
   Function1( <string>, <number> );
   Function1( <string>, <number> );
   Function2(); // Line comment
   Function3([<number|string>])
   {
     // can use data1; here if the last two parameters are
     // not-relevant, NULL or use default settings
     data1,"data1",flags;
     data2,"data2",flags;
     data3,"data3",flags;
   }
   Function4( <string> ) [
Data here is passed straight to output as formatted
]
}

When FunctionX is encountered the values or pointers to values are 
stored in a structure specific to that function and are later used to 
create the desired output. A function may be used multiple times to 
declare different 'things' of the same type. Here's a working example 
made up on the spot that could be useful for rapid development of 
command line tools. It accepts a number of useful parameters including 
and when compiled would create a complete program shell in C for the 
described application.

cligen(0)
{

   CLIName("MyProg");
   Version("1.00","01-01-1900");
   Usage("ValidateOptions();","[-i] <input> [[-o] <outfile>] [-h]");
   Parameters()
   {
     "o","output",Optional,1,"OutFile";
     "i","input",Required,1,"InFile";
     "h","help",Optional,0,,"Help();";
   }
   // Whitespace is only significant inside [] blocks
   Inline() [
void Help(void) {
   printf("Hello, World!\n");
}
]
}

Any suggestions for tools that I can use which would be appropriate for 
generating parsers for languages of this type? They should not be too 
difficult to learn as I want to spend the time porting the code rather 
than spending months working out how to use the parser generator. I have 
looked into yacc and bison but these don't seem to be appropriate and 
appear to have a huge learning curve.

The worst case scenario and what I am currently facing is that I will 
need to write a scripting language of the above type that creates the C 
source code of scripting languages of the above type.

Help is muchly appreciated as I am currently deadlocked,
Jon Ripley
-- 
http://jonripley.com/

.