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https://issues.apache.org/jira/browse/JEXL-302?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16856126#comment-16856126
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Henri Biestro commented on JEXL-302:
------------------------------------
I'm sorry, I must have been unclear; let me try again.
The intended purpose of getVariable is to retrieve the list of variables
susceptible to change the outcome of a script/expression evaluation. The output
is a set of list of strings. Each list is at least a (top level) variable
followed by properties; if one of this list is {{\{"a", "b"\}}}, it means if
there is a solvable variable {{'a'}} - and more precisely a solvable property
{{"b"}} of a variable {{"a"}}, varying its value is susceptible to change the
outcome of the script evaluation. If one list is {{\{"a", "b", "c"\}}}, it
means the solvable property {{"c"}} of the solvable property {{"b"}} of the
solvable variable {{"a"}} may have an effect etc. You get the idea.
It also means in that latest form case, that {{a['b']['c']}} may behave the
same way and thus generates the same list..
A side effect is that the method also picks up the (evil) antish-variables but
I suspect (and hope) anyone using those in their environment knows them and
should have no difficulty reconciling the output of getVariables and the
potential antish vars.
As for you example, {{a[b]['c']}} is not equivalent to {{a[b.c]}} ; the latter
is equivalent to {{a[b['c']]}}. I've added 2 more examples in VarTest.testRefs
(
https://github.com/apache/commons-jexl/commit/66d5f6e69992a6473c94bff2cf17889a428ab622
).
All that being said, I think the feature still works as intended (per
JEXL-113). But I hear you, things have changed wrt to property/array resolution
so we may want to add an option to that feature to only consider dotted
identifiers - not their array counterparts. That's fairly easy (Engine.java,
lline 588, add a condition), we just need to specify how to pass it down. I
prototried with a boolean argument to getVariable, that works but changes lots
of code, adding overloads; may be the Engine could be configured through an
option since it is probably related to resolver strategies.
Share your thoughts.
> JexlScript.getVariables returns strange values for array access
> ---------------------------------------------------------------
>
> Key: JEXL-302
> URL: https://issues.apache.org/jira/browse/JEXL-302
> Project: Commons JEXL
> Issue Type: Bug
> Affects Versions: 3.1
> Reporter: Dmitri Blinov
> Assignee: Henri Biestro
> Priority: Minor
> Fix For: 3.2
>
>
> I can not understand the logic behind the current implementation of
> {{JexlScript.getVariables()}} method. From the documentation we know that the
> result should be the set of script variables. For the code
> {code:java}
> a[b][c]{code}
> it gives three variables {{a}}, {{b}}, {{c}}. So far so good. But for the code
> {code:java}
> a[b]['c']{code}
> it returns {{a}} and {{b c}}, where second variable has two fragments {{b}}
> and {{c}}. The documentation states that variables with multiple fragments
> are ant-ish variables, but I don't have any of ant-ish variables in the
> example, and {{'c'}} is not a variable, but a constant. I expect to get {{a}}
> and {{b}} as a result.
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