feat(string): new builtin string:utf8len

Author: SuperFola

String.ark

@@ -68,6 +68,15 @@
 # @author https://github.com/SuperFola
 (let removeAt (fun (_str _index) (builtin__string:removeAt _str _index)))
 
+# @brief Compute the length of an UTF8 string by counting the number of codepoints
+# @param char a String
+# =begin
+# (string:utf8len "h")  # 1
+# (string:utf8len "🏳️‍⚧️")  # 5
+# =end
+# @author https://github.com/SuperFola
+(let utf8len (fun (_str) (builtin__string:utf8len _str)))
+
 # @brief Get the ordinal of a given character
 # @param char a String with a single UTF8 character
 # =begin

tests/string-tests.ark

@@ -38,8 +38,16 @@
     (test:eq (string:emptyOrWhitespace? "a ") false)
     (test:eq (string:emptyOrWhitespace? " a ") false) })
 
+  (test:case "utf8len" {
+    (test:eq (builtin__string:utf8len "hello") (string:utf8len "hello"))
+    (test:eq (string:utf8len "h") 1)
+    (test:eq (string:utf8len "hello") 5)
+    (test:eq (string:utf8len "hello\t") 6)
+    (test:eq (string:utf8len "🏳️‍⚧️") 5) })
+
   (test:case "ord, chr" {
     (test:eq (builtin__string:ord "a") (string:ord "a"))
+    (test:eq (string:ord "ø") 248)
     (test:eq (builtin__string:chr 65) (string:chr 65)) })
 
   (test:case "count" {