iif expression (ternary) for (c)simple language

[ammachado]

Description

This pull request adds a new expression to Simple language, IIF, which works as a ternary.

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[gnodet]

A few javadoc improvements and this empty method which needs to be removed I think.

[davsclaus]

Oh the simple language is as its name intended for simpler programming. We do not have control loops in the language, so adding iif when there is no if is a bit strange.

I guess the java standard with ? and : is tricky, and there is no grammar files for simple.

How often do you need this and do you have real-world use-cases where it would be good to have.

The groovy language is already support and works great for more power.

[ammachado]

I'm proposing this change because I've been working with a lot of projects that are using the Choice DSL to set headers/properties variables on a ternary-like fashion. Refactoring the choice block as a Groovy expression is definitely an option, but I was looking for a solution that did not requires extra dependencies.

[davsclaus]

https://issues.apache.org/jira/browse/CAMEL-21081

[davsclaus]

Okay I created a ticket - its good to have this functionality (see JIRA)

[davsclaus]

Replaced by new PR: #15168