Change to curly brace interpolation

[bcardarella]

This is some of the laziest code I've ever written. But it works and doesn't require us to write our own tokenizer, interpolation handlers, and compiler for quoted output

[bcardarella]

@NduatiK any concerns with this implementation? We can replace with a more robust parser in the future but right now this seems OK unless you have a good argument against

[bcardarella]

the alternative to { .. } would be a more pure mustache syntax: {{ .. }} which I am very certain we're guaranteed not to have any syntax conflicts. But I am also fairly certain the two character synxtax will be OK as well

[NduatiK]

@bcardarella , this works, but would benefit from us supporting escaping:

    compiled_rules =
      rules
        # Replace { that is not escaped with slash
        |> String.replace(~r|([^\\]){|, "\\g{1}<%=")
        # Replace } that is not escaped with slash
        |> String.replace(~r|([^\\])}|, "\\g{1}%>")
        # Unescape {
        |> String.replace("\\{", "{")
        # Unescape }
        |> String.replace("\\}", "}")      
        |> EEx.compile_string()

This means that:	Example 1	Example 2
"rule-{ number_2 }"	"rule-{ text <> \"\\{abc\\}\" }"
"rule-<%= number_2 %>"	"rule-<%= text <> \"{abc}\" %>"

We escape with "\{" instead of "{" because for some reason, "{" is equal to "{" in Elixir.

---

The above might be overkill, but it ensures we have an escape route if necessary eg if someone wants to include curly braces in the placeholder of a textfield

[bcardarella]

I considered adding escaping but I don't have a use case for it. If you can provide one we can add it otherwise I'd prefer not to increase surface area unnecessarily. If a UI's styles needed the { .. } syntax I don't want to go the route of escaping to permit that.

[bcardarella]

:+1: we can always add later if the need arises 😄