Consider implementing a "true" ternary operator

[springcomp]

Most languages do have a ternary operator that is akin to an if-then-else syntax as a single statement.
For instance, many languages do have the following syntax:

<condition> ? <true-result> : <false-result>

Unfortunately JMESPath does not have a ternary operator.
The closest approximation suffers from a limitation that makes it not really a true ternary operator.

Please, consider introducing ternary operator to the language.

[gibson042]

Although I think adding true-ternary syntax (or even more general if/else/switch/case/etc.) is worthwhile, it is actually possible to achieve the functionality right now with an array-wrapping trick.

(`false` && [`0`] || [`null`])[0] 
// => `null`

(`true` && [`0`] || [`null`])[0] 
// => `0`

[springcomp]

@gibson042 are you saying 'it is probably worth' or are you advising against it ?

[gibson042]

Clarified; this is a gap worth addressing.

[springcomp]

Ternary Operator Expression

This is a work-in-progress draft for an upcoming proposal to introduce a ternary operator (or expression) to the language. Please, use this discussion page to discuss the merits and other finer points about this draft.

Abstract

Motivation

From Gitter’s @hell_racer comment "I've used similar 'object-wrapping' trick before :), but I wasn't aware of this one. Thanks! That said, I think it might be a bit difficult for junior developers to grasp, so having the ternary operator would still be a nice addition." (emphasis, mine).

Grammar Changes

The following updates to the grammar support a ternary operation:

expression =/ ternary-expression

ternary-expression = expression "?" expression ":" expression

// TODO discuss precedence

Compliance Tests

Alternatives

// TODO: this page discussioncomment-11824335
// TODO: wiki