{{#with <value that's false> as |bar|}} block isn't rendered

[shawnam]

Maybe this is expected. The docs didn't seem to answer this particular scenario.

I put together a fiddle here:
https://jsfiddle.net/oo3qq3nx/1/

Specifically, I was expecting

{{#with asetting as |bar|}}
   foo {{bar}} 
{{/with}}

to render

foo false

or maybe

foo

The fact that it wasn't rendered at all was unexpected to me. I'm not sure if this is a bug or simply unclear in the docs.

[damncabbage]

It's explicitly checking for empty arrays, null, undefined, false (but not 0), and rendering any provided {{else}} block instead.

From your example:

  {{#with asetting as |bar|}}
    foo {{bar}} 
  {{else}}
    quux
  {{/with}}

It will print quux instead of the blank line it currently prints.

Whether that's a good idea is up for grabs, but at the very least this appears to be working as intended.

[danielsharvey]

It does seem to be operating as coded, but this behaviour does not appear to be covered in the documentation, and seems unexpected to my read.

The documentation says:

You might find a helper like this useful if a section of your JSON object contains deeply nested properties, and you want to avoid repeating the parent name. The above template could be useful with a JSON like ...

That is, the use case is aliasing as a way to avoid repeating the parent name. My expectation was that the contents would be rendered in all cases.

From the code I can see the else case, but this seems unintuitive in the context of the aliasing use case and is not documented.

For my 2c, I suggest removing the else case and having the contents rendered in all cases.

[nknapp]

It has been introduced here. There was no discussion, no complaint.
I doubt this will be reverted now. You probably should write your own helper supporting your semantics.

[danielsharvey]

Thanks @nknapp for the link to the pull request, which does explain things. And yes, I have already written my own handler :)

My interest is confirming intended usage and documenting it - I'd not seen the pull request you reference, which makes sense, although the documentation does not reflect this usage pattern.

Perhaps the suggestion should be for a {{#define}} helper or similar. My use case is similar to the documentation for with, except that I have multiple levels of contexts and so tracking the ../../../this etc becomes painful. Use of the with helper enables aliasing that works without the need for lots of ../'s which continually need adjusting if another level is introduced.

For example, I use the following to alias parameters to an inline partial:

{#*inline "reportHeaderRowGroup"}}
{{#with src as |src|}}
{{#with ../rowSpanContainer as |rowSpanContainer|}}
{{#with ../../dataRow as |dataRow|}}
{{#with ../../../reportData as |reportData|}}
...

Thoughts/suggestions?

[nknapp]

Closing due to inactivity. This is also now covered by examples in the documentation.