Edson,
On 6 May 2011 01:14, Edson Tirelli <ed.tirelli@gmail.com> wrote:
Wolfgang,These are remaining bugs that must be fixed before final. Goal is to support free form expressions as long as they return a boolean value (for traditional constraints), or any value (for positional). Period.
Edson2011/5/5 Wolfgang Laun <wolfgang.laun@gmail.com>
In the 5.2.0 Drools Introduction and General User Guide, there's section 2.1.3.1, Free Form expressions in Constraints (New Parser). It contains several examples:
#1 Person( age * 2 > $anotherPersonsAge + 2 )
#2 Person( addresses["home"].streetName.startsWith( "High Park" ) )
#3 Person( isAdult() )
#1 does not compile: Unable to build constraint as 'age * 2' is invalid : [Rule name='exa1']
#2 works - although I'd very much prefer not to be swamped with MVEL extensions unless I ask for it.
#3 does not compile: Unable to Analyse Expression isAdult():
[Error: no such identifier: isAdult]
[Near : {... isAdult() ....}]
Neither rule name nor line number is provided.
Would it please be possible to have a precise statement what one can write as a constraint?
<quote>
As previously we had to document the restricted limitations of a field constraint on the LHS compared to expressions used inside of an 'eval' or used on the RHS.
</quote>
I'm sorry, but I do not understand the meaning of this sentence. What does it mean, please?
Cheers
Wolfgang