cannot use ^xxx outside of match clauses

Question

This function:

defp entries(query, page_number, page_size) do
  offset = page_size * (page_number - 1)

  query
  |> limit([_], ^page_size) # error
  |> offset([_], ^offset)
  |> Repo.all
end

gives an exception:

cannot use ^pg_size outside of match clauses

Why is that and how to fix it?

Egger

Answer 1

This is most usually a sign that you haven't imported appropriate macros from Ecto.Query.

Warhol

The ones that you attempt to use: limit and offset. – Warhol

import Ecto.Query. I would strongly suggest going through elixir-lang.org/getting-started/alias-require-and-import.html and hexdocs.pm/ecto/Ecto.Query.html if you haven't already. – Warhol

Is it possible to report root cause error for this problem? – Stclair

Answer 2

Try this:

query
|> limit(page_size)
|> offset(offset)
|> Repo.all

Ladin

Answer 3

Another possible cause for this error is misspelled words. In my case it was form instead of from.

Biconvex

Answer 4

You must use ^ (pin operator - https://hexdocs.pm/elixir/Kernel.SpecialForms.html)

query
|> limit(^page_size)
|> offset(^v_offset) # I don't know if offset var override offset function of Ecto
|> Repo.all

David