Wrote Toy_Lexer, Toy_Parser API

This commit is contained in:
2023-02-16 22:38:34 +11:00
committed by GitHub
parent 48dd1f9411
commit a70149440a
4 changed files with 94 additions and 3 deletions

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c-api/toy_ast_node_h.md Normal file
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# toy_ast_node.h
This header defines the structure of the nodes used in the Abstract Syntax Tree, known as `Toy_ASTNode`. Most of what is defined here is intended for internal use, so is not documented here.
This header doesn't need to be included directly, as it is included in [toy_parser.h](c-api/toy_parser_h.md).
## Defined Functions
### void Toy_freeASTNode(Toy_ASTNode* node)
This function cleans up any valid instance of `Toy_ASTNode` pointer passed to it. It is most commonly used to clean up the values returned by `Toy_scanParser`, after they have been passsed to `Toy_writeCompiler`, or when the node is an error node.

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c-api/toy_lexer_h.md Normal file
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# toy_lexer.h
This header defines the structure `Toy_Lexer`, which can be bound to a piece of source code, and used to tokenize it within a parser.
## Defined Functions
### void Toy_initLexer(Toy_Lexer* lexer, const char* source)
This function initializes a lexer, binding it to the `source` parameter; the lexer is now ready to be passed to the parser.

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c-api/toy_parser_h.md Normal file
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# toy_parser.h
This header defines the structure `Toy_Parser` which, after being initialized with a `Toy_Lexer` produces a series of abstract syntax trees to be passed to the `Toy_Compiler`. The following is a utility function provided by [repl_tools.h](c-api/repl_tools_h.md), demonstrating how to use the parser.
```c
//generate bytecode from a given string
const unsigned char* Toy_compileString(const char* source, size_t* size) {
//declare the relevant instances
Toy_Lexer lexer;
Toy_Parser parser;
Toy_Compiler compiler;
//initialize each of them
Toy_initLexer(&lexer, source);
Toy_initParser(&parser, &lexer);
Toy_initCompiler(&compiler);
//when the parser returns NULL, it is finished
Toy_ASTNode* node = Toy_scanParser(&parser);
while(node != NULL) {
//if the parser returns an error node, clean up and exit gracefully
if (node->type == TOY_AST_NODE_ERROR) {
Toy_freeASTNode(node);
Toy_freeCompiler(&compiler);
Toy_freeParser(&parser);
//no need to clean the lexer
return NULL;
}
//write the node to the compiler
Toy_writeCompiler(&compiler, node);
Toy_freeASTNode(node);
//grab the next node
node = Toy_scanParser(&parser);
}
//get the bytecode to be returned
const unsigned char* tb = Toy_collateCompiler(&compiler, size);
//cleanup
Toy_freeCompiler(&compiler);
Toy_freeParser(&parser);
//no need to clean the lexer
//finally
return tb;
}
```
This header also includes [toy_ast_node.h](c-api/toy_ast_node_h.md), so the `Toy_freeASTNode` function can also be used.
## Defined Functions
### void Toy_initParser(Toy_Parser* parser, Toy_Lexer* lexer)
This function initializes a `Toy_Parser`, binding the given `Toy_Lexer` to it.
### void Toy_freeParser(Toy_Parser* parser)
This function frees a `Toy_Parser` once its task is completed.
### Toy_ASTNode* Toy_scanParser(Toy_Parser* parser)
This function returns an abstract syntax tree representing part of the program, or an error node. The abstract syntax tree must be passed to `Toy_writeCompiler` and/or `Toy_freeASTNode`.
This function should be called repeatedly until it returns `NULL`, indicating the end of the program.

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* [Testing Toy](deep-dive/testing-toy)
* [Roadmap](deep-dive/roadmap)
# Full C API
# Public C API
* [toy_ast_node.h]
* [repl_tools.h]
* [toy_ast_node.h](c-api/toy_ast_node_h.md)
* [toy_common.h](c-api/toy_common_h.md)
* [toy_compiler.h]
* [toy_interpreter.h]
* [toy_lexer.h]
* [toy_lexer.h](c-api/toy_lexer_h.md)
* [toy_literal_array.h]
* [toy_literal_dictionary.h]
* [toy_literal.h]