commons-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Dmitri Blinov (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (JEXL-295) Add unary plus operator
Date Fri, 29 Mar 2019 10:50:00 GMT

    [ https://issues.apache.org/jira/browse/JEXL-295?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16804807#comment-16804807
] 

Dmitri Blinov commented on JEXL-295:
------------------------------------

Since the unary plus operator can be overloaded, and overloaded implementation may not necessarily
be deterministic, I think it's not safe in general case to cache the evaluation result of
this operator even for a constant operand

> Add unary plus operator
> -----------------------
>
>                 Key: JEXL-295
>                 URL: https://issues.apache.org/jira/browse/JEXL-295
>             Project: Commons JEXL
>          Issue Type: New Feature
>    Affects Versions: 3.1
>            Reporter: Henri Biestro
>            Assignee: Henri Biestro
>            Priority: Major
>             Fix For: 3.2
>
>
> WHAT
> Introduce a new operator, the unary plus as in '+4' or '+b' expressions. JEXL arithmetic
already allows using a unary minus operator (the negate operation) so there is logic in having
the counterpart.
> The proposed default behaviour would be to:
> - call the 'Math.abs(...)' method for numbers
> - return true for boolean 
> - could uppercase strings ? (should '-' lowercase strings ??)
> HOW
> - Follow the unary minus syntax and construct in the .jjt / ASTUnaryPlus / ParserVisitor
> - Implement Interpreter, Debugger
> - Implement abs in JexlArithmetic



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)

Mime
View raw message