phlogiston.assembler.assembler source code

1 /**
2  * Interface for assembling a string of assembly containing into bytecode.
3  *
4  * Copyright © 2016, Eric Scrivner
5  *
6  * License: Subject to the terms of the MIT license, as written in the included
7  * LICENSE.txt file.
8  * Authors: Eric Scrivner
9  */
10 module phlogiston.assembler.assembler;
11 
12 import std.exception;
13 import std..string;
14 
15 import phlogiston.assembler.parser;
16 import phlogiston.assembler.scanner;
17 
18 /// Error raised if an error is encountered while assembling code.
19 class AssemblerError : Exception {
20     @safe pure nothrow this(string msg,
21                             string file = __FILE__,
22                             size_t line = __LINE__,
23                             Throwable next = null)
24         {
25             super(msg, file, line, next);
26         }
27 }
28 
29 /// Interface for parsing assembly code into bytecode
30 class Assembler {
31     /**
32      * This routine takes a string of assembly code and produces the bytecode
33      * corresponding to it.
34      *
35      * Throws: AssemblerError if an error is encountered during assembly.
36      *
37      * Params:
38      *     assemblyCode = The assembly code
39      *
40      * Returns: The bytecode resulting from compiling the assembly code.
41      */
42     public ubyte[] assemble(ref string assemblyCode) {
43         ubyte[] byteRepresentation = cast(ubyte[])assemblyCode.representation;
44 
45         Scanner scanner = new Scanner(byteRepresentation);
46         Parser parser = new Parser;
47 
48         try {
49             return parser.parse(scanner);
50         } catch(InvalidTokenException ite) {
51             throw new AssemblerError(ite.msg);
52         } catch(ParseError pe) {
53             throw new AssemblerError(pe.msg);
54         }
55     }
56 }