Update compiling-toy.md

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2023-02-07 00:44:03 +11:00
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commit c326ae465d

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@@ -26,8 +26,8 @@ bytecode -> interpreter -> result
Exactly how the source code is loaded into memory is left up to the user, however once it's loaded, it can be bound to a `Lexer` structure.
```c
Lexer lexer;
initLexer(&lexer, source);
Toy_Lexer lexer;
Toy_initLexer(&lexer, source);
```
The lexer, when invoked, will break down the string of characters into individual `Tokens`.
@@ -36,20 +36,20 @@ The lexer does not need to be freed after use, however the source code does.
## Parser
The `Parser` structure takes a `Lexer` as an argument when initialized.
The `Toy_Parser` structure takes a `Toy_Lexer` as an argument when initialized.
```c
Parser parser;
initParser(&parser, &lexer);
Toy_Parser parser;
Toy_initParser(&parser, &lexer);
ASTNode* node = scanParser(&parser);
Toy_ASTNode* node = Toy_scanParser(&parser);
freeParser(&parser);
Toy_freeParser(&parser);
```
The parser takes tokens, one at a time, and converts them into structures called Abstract Syntax Trees, or ASTs for short. Each AST represents a single top-level statement within the Toy script. You'll know when the parser is finished when `scanParser()` begins returning `NULL` pointers.
The parser takes tokens, one at a time, and converts them into structures called Abstract Syntax Trees, or ASTs for short. Each AST represents a single top-level statement within the Toy script. You'll know when the parser is finished when `Toy_scanParser()` begins returning `NULL` pointers.
The AST Nodes produced by `scanParser()` must be freed manually, and the parser itself should not be used again.
The AST Nodes produced by `Toy_scanParser()` must be freed manually, and the parser itself should not be used again.
## Compiler
@@ -57,14 +57,14 @@ The actual compilation phase has two steps - instruction writing and collation.
```c
size_t size;
Compiler compiler;
Toy_Compiler compiler;
initCompiler(&compiler);
writeCompiler(&compiler, node);
Toy_initCompiler(&compiler);
Toy_writeCompiler(&compiler, node);
unsigned char* tb = collateCompiler(&compiler, &size);
unsigned char* tb = Toy_collateCompiler(&compiler, &size);
freeCompiler(&compiler);
Toy_freeCompiler(&compiler);
```
The writing step is the process in which AST nodes are compressed into bytecode instructions, while literal values are extracted and placed aside in a cache (usually in an intermediate state).
@@ -75,17 +75,17 @@ The Toy bytecode (abbreviated to `tb`), along with the `size` variable indicatin
This bytecode can be saved into a file for later consumption by the host at runtime - ensure that the file has the `.tb` extension.
The bytecode loaded in memory is consumed and freed by `runInterpreter()`.
The bytecode loaded in memory is consumed and freed by `Toy_runInterpreter()`.
## Interpreter
The interpreter acts based on the contents of the bytecode given to it.
```c
Interpreter interpreter;
initInterpreter(&interpreter);
runInterpreter(&interpreter, tb, size);
freeInterpreter(&interpreter);
Toy_Interpreter interpreter;
Toy_initInterpreter(&interpreter);
Toy_runInterpreter(&interpreter, tb, size);
Toy_freeInterpreter(&interpreter);
```
Exactly how it accomplishes this task is up to it - as long as the result matches expectations.