ysccf

Yanang's simple compiler of compiler framwork with a simple GUI inplemented using Qt 5.
颜昂的文法编译器框架，用Qt5实现了简易的图形界面。

A simple LR(0) grammar's parser has been implemented and testified.
已实现验证LR(0)文法的解析。

LALR(1) parser and code generation are in progress.
计划实现LALR(1)文法的解析与代码生成。

Todo：

文法编译器：

• 实现属性（AttributedStatement）

[ignore]
%token space "\s+"
...
<classDefinition> ::= 
        "class"
        identifier -> [userDefinedType("definedClassName")] 
        <definitionBody>
        ";"
        ;
// 当依据这条产生式规约时可以读取到对应identifier的token加入自定义类型表
// token类型转化为definedClass而不再是identifier
// 然后在接下来的词法解析中得以应用
<variableDefinition> ::= 
        <definedClassName>
        identifier
        ";"
        ;

<producer> ::= beforeVn [userDefinedType]identifier afterVn;

• 实现一些语法糖

before	after
<rule> ::= <producer> deducer <produced> <orProduced> delimiter; <orProduced> ::= or <produced> <orProduced> | null;	<rule> ::= <producer> deducer <produced>+ delimiter;

• 加强的递归展开（可以引入[inline]属性），指示当前符号会直接在其所有引用位置展开

before	after
─── statement └── rule ├── producer │ └── VnExpr │ ├── beforeVn │ ├── userDefinedType(SomeVnName) │ └── afterVn ├── deducer ├── produced // 现在可以通过链式展开， │ ├── ... // 将非终结符下重复出现的其它递归项展开 │ └── ... ├── orProduced │ ├── produced // 但是从语义上来说， │ │ ├── ... // orProduced的子节点应该直接展开到上一层 │ │ └── ... │ └── produced // 不过递归的非终结符需要指引才能在上一层就完成展开 │ ├── ... │ └── ... └── delimiter	─── statement └── rule ├── producer │ └── VnExpr │ ├── beforeVn │ ├── userDefinedType(SomeVnName) │ └── afterVn ├── deducer ├── produced // 即 <produced>* │ ├── ... │ └── ... ├── produced │ ├── ... │ └── ... ├── produced │ ├── ... │ └── ... └── delimiter

• compilerFrontendParallel，使用队列实现词法和文法解析的并行执行

before	lexer -> custom steps -> parser -> custom steps -> user
after	lexer -> custom steps -> token queue fetched from token queue -> custom steps -> parser -> custom steps -> user

• 算符分析方法