Reverse not implemented correctly

[DavidtheGoliath]

When trying to reverse this JSON
[
{
"Key": "2",
"A": "B"
},
{
"Key": "1",
"A": "B"
}
]
array we get this error [<list_reverseiterator object at 0x3eb14f722f70>]

[pwwang]

Are you using the standard mode?

Could you share the python code how you call and render your template?

[frikky]

Are you using the standard mode?

Could you share the python code how you call and render your template?

Hey @pwwang!

We're running it in wild mode with python in the https://github.com/frikky/shuffle project, where this issue shows up. The code that runs it all can be found here: https://github.com/frikky/Shuffle/blob/581f97be8029da91ecd43c64abe1359ca1cb5a29/backend/app_sdk/app_base.py#L1767

Hope it helps! :)

[pwwang]

@frikky Thanks for providing the information. It is helpful.

We didn't implement the reverse filter. It is actually a jinja filter:

https://jinja.palletsprojects.com/en/3.0.x/templates/#jinja-filters.reverse

It returns an iterator, instead of a list. If you want a list:

>>> from liquid import Liquid, defaults
>>> defaults.MODE = 'wild'
>>> defaults.FROM_FILE = False
>>> Liquid("{{x | reverse}}").render(x=[1,2,3])
'<list_reverseiterator object at 0x7ff91960c880>'
>>> Liquid("{{x | reverse | list}}").render(x=[1,2,3])
'[3, 2, 1]'

[pwwang]

Assume it is solved. Closing.

[frikky]

Assume it is solved. Closing.

Thanks! Parsing straight to | list will indeed be our goto explainer for now.

Our docs are coming along btw. Here's an extensive list of what we aim to implement and use: Liquid docs. We will also add examples of each and every one of them long-term.

Quick Q about strings: How do you think we could solve the problem of e.g. running something with a filter, but the data is not a string? I'd ideally like to see some kind of auto-casting system, where it assumes something is a string (and e.g. adds the quotes itself), without the need of perfect information left of the pipe. Just wondering how that could be implemented well, as I'm not a parser expert ;)

[pwwang]

So here it's a little bit confusing. For example:

out = Liquid("{{ x | plus: 1}}").render(x=1)
# out == "2"
# isinstance(out, str)

Are you talking about auto-casting "2" (str) to 2 (int) for the python variable out, or are you expecting the following case to work, instead of a TypeError?

out = Liquid("{{ x | plus: 1}}").render(x="1")
# TypeError: can only concatenate str (not "int") to str