For consistency, our version of String.count should also accept regexes as patterns, as supported in String.replace and others.
*José Valimhttps://dashbit.co/ <https://dashbit.co/>* On Thu, Apr 17, 2025 at 2:28 PM Roman Smirnov <pom...@gmail.com> wrote: > Interesting. I didn't know about :binary.matches/2 > > I usually use that way to solve the original task: > Regex.scan(pattern, string) |> Enum.count > > But I guess would be nice to have a helper for it. Maybe not `count` > (could be ambiguous, b/c it's a synonym of length), maybe substr_count > > четверг, 17 апреля 2025 г. в 14:48:11 UTC+3, steffen...@dashbit.co: > >> Hello everyone, >> >> I recently came across the need to count all the occurrences of a pattern >> inside a String. First, I used `String.split(string, pattern)` and then >> counted the number of parts (-1). Then it was suggested to me to use >> `:binary.matches` instead and simply count the number of entries. This is >> quite straightforward, but you need to know about `:binary.matches`, so I >> wondered if the Elixir `String` module should include something like >> `String.count/2` instead: >> >> @doc ~S""" >> Counts the number of occurrences of a pattern in a string. >> >> ## Examples >> >> iex> String.count("hello world", "o") >> 2 >> >> iex> String.count("hello world", "l") >> 3 >> >> iex> String.count("hello world", "x") >> 0 >> >> """ >> @spec count(t, pattern) :: non_neg_integer >> @doc since: "1.19.0" >> def count(string, pattern) do >> Enum.count(:binary.matches(string, pattern)) >> end >> >> As you can see, the implementation is quite straightforward, so I'm not >> sure if it's worth to be included. Let me know what you think! >> >> Happy to send a PR. >> > -- > You received this message because you are subscribed to the Google Groups > "elixir-lang-core" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to elixir-lang-core+unsubscr...@googlegroups.com. > To view this discussion visit > https://groups.google.com/d/msgid/elixir-lang-core/0e7f4fbb-a786-4d1d-a3f9-d76712e4eae4n%40googlegroups.com > <https://groups.google.com/d/msgid/elixir-lang-core/0e7f4fbb-a786-4d1d-a3f9-d76712e4eae4n%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "elixir-lang-core" group. To unsubscribe from this group and stop receiving emails from it, send an email to elixir-lang-core+unsubscr...@googlegroups.com. To view this discussion visit https://groups.google.com/d/msgid/elixir-lang-core/CAGnRm4Jmzjkz%2Bu_fxRrCxngrwZ4ELczMud23wWpjjMZ1FsdNTA%40mail.gmail.com.
