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 Thu, 28 Mar 2019 08:43:00 GMT

    [ https://issues.apache.org/jira/browse/JEXL-295?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16803704#comment-16803704
] 

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

IMHO it's very confusing for any programmer with background of java/c/c# to have unary plus
operator to change a negative number to a positive. For many years people were taught that
+x does not change sign. I know this is a legacy question, but may be we should keep basic
implementation of unary plus operator this way, while aloowing the option of overloading it
for those who want to use it other way?

> 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