ANTLR 语法中是否有保留字列表? [英] Is there a list of reserved words in ANTLR grammars?

问题描述

我最近创建了一个ANTLR3解析器规则

options : foo bar;

没有编译，我花了一些时间才发现 options 是一个保留字(AntlrWorks 指出了错误，但没有指出原因).ANTLR 中是否有保留字列表，并且在命名规则方面是否有最佳实践(这可能有助于避免这种情况)?

解决方案

ANTLR v3的保留字是:

<前>关键字 |描述---------+--------------------------------------------------------范围|动态范围的属性片段|词法分析器规则是一个辅助规则，不是解析器的真正标记词法分析器 |语法类型树 |语法类型解析器|语法类型语法 |语法头返回 |规则返回值抛出|规则抛出异常赶上|捕获规则异常终于|无论如何都要这样做选项|语法或规则选项代币 |可以用这个添加令牌；通常是虚构的记号进口|导入语法

参见:https://web.archive.org/web/20120314155217/http://www.antlr.org/wiki/display/ANTLR3/ANTLR+Cheat+Sheet(在页面末尾)

不知道命名约定"w.r.t.解析器规则(除了它们应该以小写开头，这当然不是惯例......).

I recently created an ANTLR3 parser rule

options : foo bar;

which didn't compile and it took me some time to discover that options was a reserved word (AntlrWorks indicated an error but not why). Is there a list of reserved words in ANTLR and are there best practices in naming rules (which might help avoid this)?

解决方案

The reserved words of ANTLR v3 are:

    Keyword  |  Description
    ---------+--------------------------------------------------------
    scope    |  Dynamically-scoped attribute
    fragment |  lexer rule is a helper rule, not real token for parser
    lexer    |  grammar type
    tree     |  grammar type
    parser   |  grammar type
    grammar  |  grammar header
    returns  |  rule return value(s)
    throws   |  rule throws exception(s)
    catch    |  catch rule exceptions
    finally  |  do this no matter what
    options  |  grammar or rule options
    tokens   |  can add tokens with this; usually imaginary tokens
    import   |  import grammar(s)

See: https://web.archive.org/web/20120314155217/http://www.antlr.org/wiki/display/ANTLR3/ANTLR+Cheat+Sheet (at the end of the page)

Don't know of a "naming convention" w.r.t. parser rules (other than they should start with a lower case, which is not convention, of course...).

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