diff options
| -rw-r--r-- | lib/elixir/lib/string.ex | 13 | ||||
| -rw-r--r-- | lib/elixir/pages/Typespecs.md | 6 |
2 files changed, 16 insertions, 3 deletions
diff --git a/lib/elixir/lib/string.ex b/lib/elixir/lib/string.ex index b1831f293..2ed17991c 100644 --- a/lib/elixir/lib/string.ex +++ b/lib/elixir/lib/string.ex @@ -203,9 +203,22 @@ defmodule String do is generated at runtime and does not survive compile term. """ + @typedoc """ + A UTF-8 encoded binary. + + Note `String.t()` and `binary()` are equivalent to analysis tools. + Although, for those reading the documentation, `String.t()` implies + it is a UTF-8 encoded binary. + """ @type t :: binary + + @typedoc "A UTF-8 codepoint. It may be one or more bytes." @type codepoint :: t + + @typedoc "Multiple codepoints that may be perceived as a single character by readers" @type grapheme :: t + + @typedoc "Pattern used in functions like `replace/3` and `split/2`" @type pattern :: t | [t] | :binary.cp() @conditional_mappings [:greek] diff --git a/lib/elixir/pages/Typespecs.md b/lib/elixir/pages/Typespecs.md index 26813fe87..43c379756 100644 --- a/lib/elixir/pages/Typespecs.md +++ b/lib/elixir/pages/Typespecs.md @@ -238,8 +238,8 @@ If a callback module that implements a given behaviour doesn't export all the fu Elixir's standard library contains a few frequently used behaviours such as `GenServer`, `Supervisor`, and `Application`. -## Notes +## The `string()` type -Elixir discourages the use of type `t:string/0` as it might be confused with binaries which are referred to as "strings" in Elixir (as opposed to character lists). In order to use the type that is called `t:string/0` in Erlang, one has to use the `t:charlist/0` type which is a synonym for `string`. If you use `string`, you'll get a warning from the compiler. +Elixir discourages the use of the `string()` type. The `string()` type refers to Erlang strings, which are known as "charlists" in Elixir. They do not refer to Elixir strings, which are UTF-8 encoded binaries. To avoid confusion, if you attempt to use the type `string()`, Elixir will emit a warning. You should use `charlist()`, `binary()` or `String.t()` accordingly. -If you want to refer to the "string" type (the one operated on by functions in the `String` module), use `t:String.t/0` type instead. +Note `String.t()` and `binary()` are equivalent to analysis tools. Although, for those reading the documentation, `String.t()` implies it is a UTF-8 encoded binary. |