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How to use multi line in XBlockExpression of a dsl [message #1817729]

Thu, 28 November 2019 09:47

Dimg Cim

Messages: 59
Registered: December 2015

Member

Hi,

I have a small dsl to store sql statements with variables. Currently I can define this statments in one line. Are there possibility to use the xtend multi line in XblockExpression?

My dsl looks like

Model returns Model:
	{Model}
	'package' package=QualifiedName
	
	'class' name=ID '{'
		(queries+=Query ( queries+=Query)* )?
	'}'
	;
	
Query returns Query:
	{Query}
	'Query' name=EString '(' (parameters+=JvmFormalParameter ( "," parameters+=JvmFormalParameter)* )? ')' 
		statement=XBlockExpression
	;
	
EString returns ecore::EString:
	STRING | ID;

For complex statments it is better to separate it by line breaks, but here it is ok

package hello.world
 
class QueryManager{ 
	
	Query HelloWorld(String param1){ 
		val sql = "SELECT * from Table where name = "
		sql
	}
}

How can I defined the XBlockExpression to use that

Query HelloWorld(String param1, String param2){ 
		val sql = '''SELECT * from Table 
                where name = param1 and forename = param2
                order by name asc               
'''
		sql
	}

Regards
dimg

P.S. I tried to use the

terminal STATEMENT: "'''" -> "''''";

But how can I Escape the character ' ?
Further how can I get this result as String with linebreaks in my ModelInferer?
Maybe it is better to reuse that one from Xtend Grammar

[Updated on: Thu, 28 November 2019 09:55]

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Re: How to use multi line in XBlockExpression of a dsl [message #1817731 is a reply to message #1817729]

Thu, 28 November 2019 10:05

Christian Dietrich

Messages: 14665
Registered: July 2009

Senior Member

you have to care about that yourself. (e.g. have a look what xtend does which uses jflex for lexing
p.s. do you know that "" and '' are already Multiline?

Twitter : @chrdietrich
Blog : https://www.dietrich-it.de

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Re: How to use multi line in XBlockExpression of a dsl [message #1817734 is a reply to message #1817731]

Thu, 28 November 2019 10:26

Dimg Cim

Messages: 59
Registered: December 2015

Member

Okay thanks for feedback, maybe I use this terminal STATEMENT: '```' -> '```';

And cleaned up the result in the ModelInferrer. Because the result of this description

class QueryManager{ 
	
	Query HelloWorld(String param1)```
	SELECT * from Table where name = <param1>
	```
	
}

returns the JavaCode with

@SuppressWarnings("all")
public class QueryManager {
  public static String HelloWorld(final String param1) {
    return ```
    	SELECT * from Table where name = <param1>
    	```;
  }
}

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