[jira] [Commented] (JEXL-226) add ?? operator support
[ https://issues.apache.org/jira/browse/JEXL-226?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16067622#comment-16067622 ] Min Wei commented on JEXL-226: -- This is great, Henri > add ?? operator support > > > Key: JEXL-226 > URL: https://issues.apache.org/jira/browse/JEXL-226 > Project: Commons JEXL > Issue Type: New Feature >Affects Versions: Later >Reporter: Min Wei >Assignee: Henri Biestro > Labels: features > Fix For: 3.2 > > Original Estimate: 1h > Remaining Estimate: 1h > > Jexl already supports null-coalescing semantics with the operator "?:". So it > should be a simple matter to extend it with a different syntax. > https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/operators/null-conditional-operator > https://github.com/apache/commons-jexl/pull/4 -- This message was sent by Atlassian JIRA (v6.4.14#64029)
[jira] [Commented] (JEXL-226) add ?? operator support
[ https://issues.apache.org/jira/browse/JEXL-226?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16066131#comment-16066131 ] Dmitri Blinov commented on JEXL-226: Sorry, false alarm, this is the artifact from old build :-( > add ?? operator support > > > Key: JEXL-226 > URL: https://issues.apache.org/jira/browse/JEXL-226 > Project: Commons JEXL > Issue Type: New Feature >Affects Versions: Later >Reporter: Min Wei >Assignee: Henri Biestro > Labels: features > Fix For: 3.2 > > Original Estimate: 1h > Remaining Estimate: 1h > > Jexl already supports null-coalescing semantics with the operator "?:". So it > should be a simple matter to extend it with a different syntax. > https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/operators/null-conditional-operator > https://github.com/apache/commons-jexl/pull/4 -- This message was sent by Atlassian JIRA (v6.4.14#64029)
[jira] [Commented] (JEXL-226) add ?? operator support
[
https://issues.apache.org/jira/browse/JEXL-226?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16066116#comment-16066116
]
Dmitri Blinov commented on JEXL-226:
I'm unable to use this operator in scripts. The following construct
{code}
x??true
{code}
throws org.apache.commons.jexl3.JexlException$Parsing: evalScript@1:3 parsing
error in '?'
> add ?? operator support
>
>
> Key: JEXL-226
> URL: https://issues.apache.org/jira/browse/JEXL-226
> Project: Commons JEXL
> Issue Type: New Feature
>Affects Versions: Later
>Reporter: Min Wei
>Assignee: Henri Biestro
> Labels: features
> Fix For: 3.2
>
> Original Estimate: 1h
> Remaining Estimate: 1h
>
> Jexl already supports null-coalescing semantics with the operator "?:". So it
> should be a simple matter to extend it with a different syntax.
> https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/operators/null-conditional-operator
> https://github.com/apache/commons-jexl/pull/4
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[jira] [Commented] (JEXL-226) add ?? operator support
[
https://issues.apache.org/jira/browse/JEXL-226?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16064693#comment-16064693
]
Henri Biestro commented on JEXL-226:
The Elvis operator casts the left-hand side to boolean; The 'null coalescing'
operator does not.
{code}
// x is not defined
x ?? 'other value' ; // 'other value'
var x = null;
x?? 'other value'; // 'other value'
x = 1;
x?? 'other value'; // 1
x = 0.0;
x?? 'other value'; // 0.0
x = NaN;
x??'other value'; //NaN
x ="";
x??'other value'; // ""
{code}
> add ?? operator support
>
>
> Key: JEXL-226
> URL: https://issues.apache.org/jira/browse/JEXL-226
> Project: Commons JEXL
> Issue Type: New Feature
>Affects Versions: Later
>Reporter: Min Wei
> Labels: features
> Fix For: Later
>
> Original Estimate: 1h
> Remaining Estimate: 1h
>
> Jexl already supports null-coalescing semantics with the operator "?:". So it
> should be a simple matter to extend it with a different syntax.
> https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/operators/null-conditional-operator
> https://github.com/apache/commons-jexl/pull/4
--
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[jira] [Commented] (JEXL-226) add ?? operator support
[ https://issues.apache.org/jira/browse/JEXL-226?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16064667#comment-16064667 ] Sebb commented on JEXL-226: --- Just so we are completely clear, could we please document what is expected for a null variable? And a true/non-zero variable? > add ?? operator support > > > Key: JEXL-226 > URL: https://issues.apache.org/jira/browse/JEXL-226 > Project: Commons JEXL > Issue Type: New Feature >Affects Versions: Later >Reporter: Min Wei > Labels: features > Fix For: Later > > Original Estimate: 1h > Remaining Estimate: 1h > > Jexl already supports null-coalescing semantics with the operator "?:". So it > should be a simple matter to extend it with a different syntax. > https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/operators/null-conditional-operator > https://github.com/apache/commons-jexl/pull/4 -- This message was sent by Atlassian JIRA (v6.4.14#64029)
[jira] [Commented] (JEXL-226) add ?? operator support
[
https://issues.apache.org/jira/browse/JEXL-226?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16064618#comment-16064618
]
Henri Biestro commented on JEXL-226:
Aliases we have (eq, etc...) are witnesses of a long past; I wish there was an
easy way to deprecate them...
Back to null coalescing, after carefully reviewing the various semantics
associated with '?:' and '??', it might be worth adding an actual strict 'null
coalescing' operator. It would only return the right hand side if the left hand
side is null (or undefined for a variable). The difference would be as such:
{code}
var a = false;
a ?? 'other value' ; // returns false
a ?: 'other value' ; // returns 'other value'
var b = 0;
b ?? 'other value' ; // returns 0
b ?: 'other value' ; // returns 'other value'
{code}
> add ?? operator support
>
>
> Key: JEXL-226
> URL: https://issues.apache.org/jira/browse/JEXL-226
> Project: Commons JEXL
> Issue Type: New Feature
>Affects Versions: Later
>Reporter: Min Wei
> Labels: features
> Fix For: Later
>
> Original Estimate: 1h
> Remaining Estimate: 1h
>
> Jexl already supports null-coalescing semantics with the operator "?:". So it
> should be a simple matter to extend it with a different syntax.
> https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/operators/null-conditional-operator
> https://github.com/apache/commons-jexl/pull/4
--
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[jira] [Commented] (JEXL-226) add ?? operator support
[
https://issues.apache.org/jira/browse/JEXL-226?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16064497#comment-16064497
]
Dmitri Blinov commented on JEXL-226:
Just to mention that we have aliases for relational operators like {{eq}} for
{{==}} etc. And I personally would find it more convenient and easy to read to
use {{in}} instead of {{=~}} :-)
> add ?? operator support
>
>
> Key: JEXL-226
> URL: https://issues.apache.org/jira/browse/JEXL-226
> Project: Commons JEXL
> Issue Type: New Feature
>Affects Versions: Later
>Reporter: Min Wei
> Labels: features
> Fix For: Later
>
> Original Estimate: 1h
> Remaining Estimate: 1h
>
> Jexl already supports null-coalescing semantics with the operator "?:". So it
> should be a simple matter to extend it with a different syntax.
> https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/operators/null-conditional-operator
> https://github.com/apache/commons-jexl/pull/4
--
This message was sent by Atlassian JIRA
(v6.4.14#64029)
[jira] [Commented] (JEXL-226) add ?? operator support
[ https://issues.apache.org/jira/browse/JEXL-226?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16063913#comment-16063913 ] Min Wei commented on JEXL-226: -- I know the Java heritage, though ?? is becoming a more pattern (e.g. Swift supports it too). Note that I am still experimenting with JEXL. And kind of curious about the main use cases by other people. I know it's originally planned to support SCXML Given JEXL is already departing away from Java (e.g. its lambda etc.), it might make sense to make it more "LISP like" expression language that supports defining new operators. Anyway, just a suggestion. Please feel free to close out this jira. > add ?? operator support > > > Key: JEXL-226 > URL: https://issues.apache.org/jira/browse/JEXL-226 > Project: Commons JEXL > Issue Type: New Feature >Affects Versions: Later >Reporter: Min Wei > Labels: features > Fix For: Later > > Original Estimate: 1h > Remaining Estimate: 1h > > Jexl already supports null-coalescing semantics with the operator "?:". So it > should be a simple matter to extend it with a different syntax. > https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/operators/null-conditional-operator > https://github.com/apache/commons-jexl/pull/4 -- This message was sent by Atlassian JIRA (v6.4.14#64029)
[jira] [Commented] (JEXL-226) add ?? operator support
[ https://issues.apache.org/jira/browse/JEXL-226?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16063883#comment-16063883 ] Henri Biestro commented on JEXL-226: JEXL stands for Java Expression Language though :-) Not a fan of adding a C# syntax for an operator that already exists; I'd suggest regexp/replace ?? with ?: if this is a must in your case. For operators, at least the actual operations behind the syntax, most of the behaviors (if not all) can be customized through a user-defined JexlArithmetic and overriding/overloading the corresponding methods. (see http://commons.apache.org/proper/commons-jexl/apidocs/org/apache/commons/jexl3/JexlOperator.html ) > add ?? operator support > > > Key: JEXL-226 > URL: https://issues.apache.org/jira/browse/JEXL-226 > Project: Commons JEXL > Issue Type: New Feature >Affects Versions: Later >Reporter: Min Wei > Labels: features > Fix For: Later > > Original Estimate: 1h > Remaining Estimate: 1h > > Jexl already supports null-coalescing semantics with the operator "?:". So it > should be a simple matter to extend it with a different syntax. > https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/operators/null-conditional-operator > https://github.com/apache/commons-jexl/pull/4 -- This message was sent by Atlassian JIRA (v6.4.14#64029)
[jira] [Commented] (JEXL-226) add ?? operator support
[ https://issues.apache.org/jira/browse/JEXL-226?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16063512#comment-16063512 ] Min Wei commented on JEXL-226: -- I have some internal use cases to prefer the C# like syntax. On thinking of it, it might be a good idea to be able to redefine the operators in general for a scripting language like JEXL. Because it's a DSL after all. > add ?? operator support > > > Key: JEXL-226 > URL: https://issues.apache.org/jira/browse/JEXL-226 > Project: Commons JEXL > Issue Type: New Feature >Affects Versions: Later >Reporter: Min Wei > Labels: features > Fix For: Later > > Original Estimate: 1h > Remaining Estimate: 1h > > Jexl already supports null-coalescing semantics with the operator "?:". So it > should be a simple matter to extend it with a different syntax. > https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/operators/null-conditional-operator > https://github.com/apache/commons-jexl/pull/4 -- This message was sent by Atlassian JIRA (v6.4.14#64029)
[jira] [Commented] (JEXL-226) add ?? operator support
[ https://issues.apache.org/jira/browse/JEXL-226?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16063088#comment-16063088 ] Henri Biestro commented on JEXL-226: I'm very much against having 2 syntaxes for the same operator. What is the benefit of not using the 'elvis' operator ? > add ?? operator support > > > Key: JEXL-226 > URL: https://issues.apache.org/jira/browse/JEXL-226 > Project: Commons JEXL > Issue Type: New Feature >Affects Versions: Later >Reporter: Min Wei > Labels: features > Fix For: Later > > Original Estimate: 1h > Remaining Estimate: 1h > > Jexl already supports null-coalescing semantics with the operator "?:". So it > should be a simple matter to extend it with a different syntax. > https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/operators/null-conditional-operator > https://github.com/apache/commons-jexl/pull/4 -- This message was sent by Atlassian JIRA (v6.4.14#64029)
