How do Shopify/Liquid and shopify.dev differ?

[sebastienros]

I am often using the code blocks in https://shopify.dev/docs/api/liquid#liquid_basics to test some snippets of liquid. However it seems like the results vary with this repository. Here is an example, where last and first can be used on a string, but I can't find this logic in this repository.

Another example is identifiers, where on the shopify.dev you can use $ as the first char, but in this repository the Regex for identifiers doesn't include it.

What are the reasons for these differences? Which one is correct?

[jg-rp]

As far as first and last go, they are handled here:

liquid/lib/liquid/variable_lookup.rb

Line 70 in 323951b

elsif lookup_command?(i) && object.respond_to?(key)

Best guess (hopefully someone at Shopify will correct me if I’m wrong), strings on shopify.dev are active support strings, which do respond to first and last. Where as standard Ruby strings don’t.

So it’s the string objects that are different, not the Liquid engine. 🤷