如何解决杰森没有假设正确的语法
我正在用jison创建语法
这是我的吉森文件:
sgr.jison
/*
AUX VARIABLES
*/
%{
var contratos = "(E1:ENTIDADE)-[C:CONTRATO] -> (E2:ENTIDADE)";
var dataArray = {};
function
translateQuery(dataArray)
{
var finalQuery = dataArray["Listar"] + " "
+ dataArray["Contratos"] + "\n"
+ dataArray["Onde"] + " "
+ dataArray["condition"] + "\n"
+ dataArray["Retornar"] + " "
+ dataArray["returnAttributes"]
console.log("\n" + finalQuery)
}
%}
/* description: Parses end executes mathematical expressions. */
/* lexical grammar */
%lex
%%
\s+ /* skip whitespace */
Listar return 'MATCH'
Contratos return 'CONTRACTS'
Onde return 'WHERE'
Retornar return 'RETURN'
e return 'AND'
ou return 'OR'
"," return 'DELIMITER'
";" return 'END'
[><>=<==] return 'MATH_SYMBOL'
[0-9]+\b return 'VALUE'
[A-Za-z0-9.]+\b return 'ENTITY_ATTRIBUTE'
["] return 'QUOTATION_MARK'
/lex
%start expressions
%% /* language grammar */
expressions :
regra
{
/*
ADD SOMETHING
ONLY IF NEEDED
*/
}
| /* | significa um OU o que quer dizer que isto aqui pode ter mais do que uma regra ISTO E FEITO PELA RECURSIVIDADE*/
expressions regra
{
/*
ADD SOMETHING
ONLY IF NEEDED
*/
}
;
regra:
MATCH CONTRACTS
WHERE condition
RETURN returnAttributes END
{
$$ = $1 + " "
+ $2 + " "
+ $3 + " "
+ $4 + " "
+ $5 + " "
+ $6 + " "
dataArray[$1] = "MATCH"
dataArray[$2] = contratos
dataArray[$3] = "WHERE"
dataArray["condition"] = $4
dataArray[$5] = "RETURN"
dataArray["returnAttributes"] = $6
/*ESTA FUNCAO TRATA DE TradUZIR A QUERY QUE E INTERPRETADA*/
translateQuery(dataArray)
}
;
condition:
ENTITY_ATTRIBUTE MATH_SYMBOL
{
$$ = $1 + " "
+ $2
}
|
condition VALUE
{
$$ = $1 + " "
+ $2
}
|
condition QUOTATION_MARK ENTITY_ATTRIBUTE QUOTATION_MARK
{
$$ = $1 + " "
+ $2 + " "
+ $3 + " "
+ $4
}
|
condition AND ENTITY_ATTRIBUTE MATH_SYMBOL VALUE
{
$$ = $1 + " "
+ $2 + " "
+ $3 + " "
+ $4 + " "
+ $5
}
|
condition OR ENTITY_ATTRIBUTE MATH_SYMBOL VALUE
{
$$ = $1 + " "
+ $2 + " "
+ $3 + " "
+ $4 + " "
+ $5
}
|
condition AND ENTITY_ATTRIBUTE MATH_SYMBOL QUOTATION_MARK ENTITY_ATTRIBUTE QUOTATION_MARK
{
$$ = $1 + " "
+ $2 + " "
+ $3 + " "
+ $4 + " "
+ $5 + " "
+ $6 + " "
+ $7
}
|
condition OR ENTITY_ATTRIBUTE MATH_SYMBOL QUOTATION_MARK ENTITY_ATTRIBUTE QUOTATION_MARK
{
$$ = $1 + " "
+ $2 + " "
+ $3 + " "
+ $4 + " "
+ $5 + " "
+ $6 + " "
+ $7
}
;
returnAttributes:
ENTITY_ATTRIBUTE
{
$$ = $1
}
|
returnAttributes DELIMITER ENTITY_ATTRIBUTE
{
$$ = $1 + ""
+ $2 + " "
+ $3
}
;
在我的词汇语法定义中,我具有:
e return 'AND'
ou return 'OR'
因此,每当在我的测试文件中找到“ e”或“ ou”时,它们都应分别返回“ AND”和“ OR”。
问题是,当我对其进行测试时,不是返回“ AND”和“ OR”,而是返回了“ e”和“ ou”。
看看:
这是我的测试文件:
test.sgr
Listar Contratos
Onde C.preco=1000
Retornar C.Preco,C.NifAdjudicante,C.NifAdjudicataria;
Listar Contratos
Onde C.preco=1000 e E1.name="ESTG"
Retornar C.Preco,C.NifAdjudicataria;
Listar Contratos
Onde C.preco=1000 e E1.name="ESTG" e C.TipoProcedimento="ADS"
Retornar C.Preco,C.NifAdjudicataria;
Listar Contratos
Onde E1.name="ESTG"
Retornar E1.name,C.Preco,C.NifAdjudicataria;
Listar Contratos
Onde E1.name="ESTG" e C.preco=1000 ou C.preco>1000
Retornar E1.name,C.NifAdjudicataria;
输出应为:
MATCH (E1:ENTIDADE)-[C:CONTRATO] -> (E2:ENTIDADE)
WHERE C.preco = 1000
RETURN C.Preco,C.NifAdjudicataria
MATCH (E1:ENTIDADE)-[C:CONTRATO] -> (E2:ENTIDADE)
WHERE C.preco = 1000 AND E1.name = " ESTG "
RETURN C.Preco,C.NifAdjudicataria
MATCH (E1:ENTIDADE)-[C:CONTRATO] -> (E2:ENTIDADE)
WHERE C.preco = 1000 AND E1.name = " ESTG " AND C.TipoProcedimento = " ADS "
RETURN C.Preco,C.NifAdjudicataria
MATCH (E1:ENTIDADE)-[C:CONTRATO] -> (E2:ENTIDADE)
WHERE E1.name = " ESTG "
RETURN E1.name,C.NifAdjudicataria
MATCH (E1:ENTIDADE)-[C:CONTRATO] -> (E2:ENTIDADE)
WHERE E1.name = " ESTG " AND C.preco = 1000 OR C.preco > 1000
RETURN E1.name,C.NifAdjudicataria
但是输出是:
我做错了什么?
解决方法
在词汇分析器中标识的
令牌具有令牌类型(这是您从扫描程序操作返回的字符串)以及匹配的文本,该文本由词汇扫描程序保留在其yytext
属性中解析器从中初始化令牌的语义值。 (文档对此没有很好的描述。)
所以在此操作中:
condition:
condition OR ENTITY_ATTRIBUTE MATH_SYMBOL VALUE
{
$$ = $1 + " "
+ $2 + " "
+ $3 + " "
+ $4 + " "
+ $5
}
$2
的值是令牌类型为"OR"
的令牌所匹配的文本。如果您需要字符串ou
,那么应该在操作中添加以下内容:
"OR"
(话虽如此,我不得不说,我认为有更好的方法来构建AST。但是,如果这种方法对您有用,那就太酷了。)
版权声明:本文内容由互联网用户自发贡献,该文观点与技术仅代表作者本人。本站仅提供信息存储空间服务,不拥有所有权,不承担相关法律责任。如发现本站有涉嫌侵权/违法违规的内容, 请发送邮件至 dio@foxmail.com 举报,一经查实,本站将立刻删除。