1 files changed, 79 insertions, 0 deletions
diff --git a/src/str.gleam b/src/str.gleam
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+++ b/src/str.gleam
@@ -0,0 +1,79 @@
+// Named str to avoid name collisions with the Erlang string module.
+// Will rename later once we have namespaces for modules.
+
+import expect
+import iodata
+import list
+
+pub external fn length(String) -> Int = "string" "length"
+
+test length {
+  length("ß↑e̊")
+  |> expect:equal(_, 3)
+
+  length("Gleam")
+  |> expect:equal(_, 5)
+
+  length("")
+  |> expect:equal(_, 0)
+
+  // TODO: This crashes.
+  // length("é")
+  // |> expect:equal(_, 1)
+}
+
+pub external fn lowercase(String) -> String = "string" "lowercase"
+
+test lowercase {
+  lowercase("Gleam")
+  |> expect:equal(_, "gleam")
+}
+
+pub external fn uppercase(String) -> String = "string" "uppercase"
+
+test uppercase {
+  uppercase("Gleam")
+  |> expect:equal(_, "GLEAM")
+}
+
+pub fn reverse(string) {
+  string
+  |> iodata:new
+  |> iodata:reverse
+  |> iodata:to_string
+}
+
+test reverse {
+  reverse("Gleam")
+  |> expect:equal(_, "maelG")
+}
+
+pub fn split(string, on) {
+  string
+  |> iodata:new
+  |> iodata:split(_, on)
+  |> list:map(_, iodata:to_string)
+}
+
+test split {
+  "Gleam,Erlang,Elixir"
+  |> split(_, ",")
+  |> expect:equal(_, ["Gleam", "Erlang", "Elixir"])
+
+  "Gleam, Erlang,Elixir"
+  |> split(_, ", ")
+  |> expect:equal(_, ["Gleam", "Erlang,Elixir"])
+}
+
+pub fn replace(string, pattern, with) {
+  string
+  |> iodata:new
+  |> iodata:replace(_, pattern, with)
+  |> iodata:to_string
+}
+
+test replace {
+  "Gleam,Erlang,Elixir"
+  |> replace(_, ",", "++")
+  |> expect:equal(_, "Gleam++Erlang++Elixir")
+}