ANTLR是否在locals子句中允许多个变量定义? [英] Does ANTLR allow multiple variable definitions in the locals clause?
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问题描述
在解析器语法中,我想在
locals
子句.
in a Parser Grammar I'd like to define several variables in the
locals
clause.
一个简化的示例如下:
body
locals [
Map<String, String> bodyContent = new HashMap<String, String>();
long counter = 0;
]
: BODY_CAPTION NEWLINE line ;
line : key='MyKey' TAB value='MyValue' NEWLINE
{
$body::bodyContent.put($key.text, $value.text);
$body::counter++;
} ;
这给出了错误:
unknown attribute 'counter' for rule 'body' in '$body::counter'
如果我像这样交换locals
子句中的行
If I swap the lines in the locals
clause like this
locals [
long counter = 0;
Map<String, String> bodyContent = new HashMap<String, String>();
]
它给出了错误:
unknown attribute 'bodyContent' for rule 'body' in '$body::bodyContent'
显然,ANTLR仅识别locals
子句中的第一个局部变量定义.
Apparently, ANTLR recognizes only the first local variable definition in the locals
clause.
有没有办法在locals
下定义多个局部变量?
Is there a way, to define multiple local variables under locals
?
推荐答案
是的,但是它们像参数列表和returns
子句一样以逗号分隔.
Yes, but they are comma separated like the parameter list and returns
clause.
locals [
Map<String, String> bodyContent = new HashMap<String, String>(),
long counter = 0
]
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